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2<h3>BKG Ntrip Client (BNC) Version 2.7 Manual</h3>
3
4<p>
5The BKG Ntrip Client (BNC) is a program for simultaneously retrieving, decoding, converting and processing real-time GNSS data streams. It has been developed within the framework of the IAG sub-commission for Europe (EUREF) and the International GNSS Service (IGS). Although meant as a real-time tool, it comes with some Post Processing functionality. You may like to use it for data coming from NTRIP Broadcasters like
6<u>http://www.euref-ip.net/home</u>,
7<u>http://www.igs-ip.net/home</u>,
8<u>http://products.igs-ip.net/home</u>, or
9<u>http://mgex.igs-ip.net/home</u>.
10</p>
11
12<p>
13BNC has been written under GNU General Public License (GPL). Source code is available from Subversion software archive <u>http://software.rtcm-ntrip.org/svn/trunk/BNC.</u> Binaries for BNC are available for Windows, 32-bit Linux, 64-bit Linux (compiled under -m32 32-bit compatibility mode), Solaris, and Mac systems. We used the MinGW Version 4.4.0 compiler to create the Windows binary. It is likely that BNC can be compiled on other systems where a GNU compiler and Qt Version 4.7.3 are installed. Please ensure that you have installed the latest version of BNC available from <u>http://igs.bkg.bund.de/ntrip/download</u> and feel free to send us your comments, suggestions or bug reports.
14</p>
15
16<p><b>Contents</b><br>
17<a href=#purpose>1. Purpose</a><br>
18<a href=#opthandling>2. Handling</a><br>
19<a href=#optsettings>3. Settings</a><br>
20<a href=#limits>4. Limitations</a><br>
21<a href=#annex>5. Annex</a>
22</p>
23
24<p>
25<b><a name="authors">Authors</b><br>
26The BKG Ntrip Client (BNC) and its Qt graphic user interface has been developed for
27</p>
28<p>
29Georg Weber<br>
30Federal Agency for Cartography and Geodesy (BKG)<br>
31Department of Geodesy<br>
32Frankfurt, Germany<br>
33[euref-ip@bkg.bund.de] or [igs-ip@bkg.bund.de]
34</p>
35
36<p>
37BNC has been written by
38</p>
39
40<p>
41Leos Mervart<br>
42Czech Technical University (CTU)<br>
43Department of Geodesy<br>
44Prague, Czech Republic
45</p>
46<p>
47BNC includes the following GNU GPL software components:
48<ul>
49<li> RTCM 2 decoder, written by Oliver Montenbruck, German Space Operations Center, DLR, Oberpfaffenhofen, Germany</li>
50<li> RTCM 3 decoder for standard messages and a RTCM 3 encoder & decoder for SSR messages, both written for BKG by Dirk Stoecker, Alberding GmbH, Schoenefeld, Germany</li>
51</ul>
52</p>
53</p>
54
55<p>
56<b>Acknowledgements</b><br>
57Earlier versions of BNC's Help Contents have been proofread by Thomas Yan, University of New South Wales, Australia. He also provided pre-compiled builds of BNC for Mac systems.<br>
58Scott Glazier, OmniSTAR Australia has been helpful in finding BNC's bugs.<br>
59James Perlt, BKG, helped fixing bugs and redesigned BNC's main window.<br>
60Andre Hauschild, German Space Operations Center, DLR, revised the RTCM Version 2 decoder.<br>
61Zdenek Lukes, Czech Technical University Prague, Department of Geodesy, extended the RTCM Version 2 decoder to handle message types 3, 20, 21, and 22 and added loss of lock indicator.<br>
62Jan Dousa, Geodetic Observatory Pecny, Czech Republic, provided a tool for drawing stream distribution maps and also helped with fixing bugs.<br>
63Denis Laurichesse, Centre National d'Etudes Spatiales (CNES), suggested synchronizing observations and clock corrections to reduce high frequency noise in PPP solutions.
64</p>
65
66<p><a name="purpose"><h3>1. Purpose</h3></p>
67
68<p> The purpose of BNC is to
69<ul>
70<li>retrieve real-time GNSS data streams available through NTRIP transport protocol,</li>
71<li>retrieve real-time GNSS data streams via TCP directly from an IP address without using the NTRIP transport protocol,</li>
72<li>retrieve real-time GNSS data streams from a local UDP or serial port without using the NTRIP transport protocol,</li>
73<li>generate high-rate RINEX Observation and Navigation files to support near real-time GNSS Post Processing applications,</li>
74<li>generate ephemeris and synchronized or unsynchronized observations epoch by epoch through an IP port to support real-time GNSS network engines,</li>
75<li>generate clock and orbit corrections to Broadcast Ephemeris through an IP port to support real-time Precise Point Positioning on GNSS rovers,</li>
76<li>generate synchronized or unsynchronized clock and orbit corrections to Broadcast Ephemeris epoch by epoch through an IP port to support the (outside) combination of such streams as coming simultaneously from various correction providers,</li>
77<li>monitor the performance of a network of real-time GNSS data streams to generate advisory notes in case of outages or corrupted streams,</li>
78<li>scan RTCM streams for incoming antenna information as well as message types and their repetition rates,</li>
79<li>feed a stream into a GNSS receiver via serial communication link,</li>
80<li>carry out a real-time Precise Point Positioning to determine a GNSS rover position,</li>
81<li>simultaneously process several Broadcast Correction streams to produce, encode and upload combined Broadcast Corrections,</li>
82<li>upload a Broadcast Ephemeris stream in RTCM Version 3 format,</li>
83<li>read GNSS clocks and orbits in a plain ASCII format from an IP port - they can be produced by a real-time GNSS engine such as RTNet and should be referenced to the IGS Earth-Centered-Earth-Fixed (ECEF) reference system. BNC will then</li>
84<ul>
85<li>convert the IGS Earth-Centered-Earth-Fixed clocks and orbits into Broadcast Corrections with radial, along-track and cross-track components,</li>
86<li>upload Broadcast Corrections as an RTCM Version 3 stream to an NTRIP Broadcaster,</li>
87<li>refer the clock and orbit corrections to a specific reference system,</li>
88<li>log the Broadcast Corrections as Clock RINEX files for further processing using other tools than BNC,</li>
89<li>log the Broadcast Corrections as SP3 files for further processing using other tools than BNC,</li>
90</ul>
91<li>edit or concatenate RINEX files or check their quality.</li>
92</ul>
93</p>
94
95<p>
96BNC supports decoding the following GNSS stream formats and message types:
97</p>
98<p>
99<ul>
100<li>RTCM Version 2 message types for GPS and GLONASS observations, </li>
101<li>RTCM Version 3 'conventional' message types for observations and Broadcast Ephemeris for GPS, GLONASS, SBAS, Galileo, COMPASS and QZSS,</li>
102<li>RTCM Version 3 'State Space Representation' (SSR) messages for GPS, GLONASS and Galileo,</li>
103<li>Drafted RTCM Version 3 'Multiple Signal Messages' (MSM) and 'High Precision Multiple Signal Messages' (HP MSM),</li>
104<li>RTNET, a plain ASCII format defined within BNC to receive orbits and clock from a serving GNSS engine.
105</ul>
106Note that up to now basic QZSS support follows a draft for RTCM MSM messages agreed by JAXA, BKG and DLR. Support of certain extra QZSS messages and support of COMPASS so far only follows an internal agreement between BKG and DLR.
107</p>
108<p>
109Furthermore, BNC allows to by-pass its decoding and conversion algorithms, leave whatever is received untouched and save it in files.
110</p>
111
112<p>
113The first of the following figures shows a flow chart of BNC connected to a GNSS receiver providing observations via serial or TCP communication link for the purpose of Precise Point Positioning. The second figure shows the conversion of RTCM streams to RINEX files. The third figure shows a flow chart of BNC feeding a real-time GNSS engine which estimates precise orbits and clocks. BNC is used in this scenario to encode correctors to RTCM Version 3 and upload them to an NTRIP Broadcaster. The fourth figure shows BNC combining several Broadcast Correction streams to disseminate the combination product while saving results in SP3 and Clock RINEX files.
114</p>
115<p><img src="IMG/screenshot10.png"/></p>
116<p><u>Figure 1:</u> Flowchart, BNC connected to a GNSS receiver for Precise Point Positioning.</p>
117
118<p>
119</p>
120<p><img src="IMG/screenshot01.png"/></p>
121<p><u>Figure 2:</u> Flowchart, BNC converting RTCM streams to RINEX batches.</p>
122
123<p>
124</p>
125<p><img src="IMG/screenshot02.png"/></p>
126<p><u>Figure 3:</u> Flowchart, BNC feeding a real-time GNSS engine and uploading encoded Broadcast Corrections.</p>
127
128<p>
129</p>
130<p><img src="IMG/screenshot19.png"/></p>
131<p><u>Figure 4:</u> Flowchart, BNC combining Broadcast Correction streams.</p>
132
133
134<p><a name="opthandling"><h3>2. Handling</h3></p>
135<p>
136Although BNC is mainly a real-time tool to be operated online, it can be run offline
137<ul>
138<li>to simulate real-time observation situations for debugging purposes,</li>
139<li>for Post Processing purposes.</li>
140</ul>
141Furthermore, apart from its regular window mode, BNC can be run as a batch/background job in a 'no window' mode using processing options from a previously saved configuration or from command line.
142</p>
143<p>
144Unless it runs offline, BNC
145</p>
146<ul>
147<li>requires access to the Internet with a minimum of about 2 to 6 kbits/sec per stream depending on the stream format and the number of visible satellites. You need to make sure that the connection can sustain the required bandwidth.</li>
148<li>requires the clock of the host computer to be properly synchronized.</li>
149<li>has the capacity to retrieve hundreds of GNSS data streams simultaneously. Please be aware that such usage may incur a heavy load on the NTRIP Broadcaster side depending on the number of streams requested. We recommend limiting the number of streams where possible to avoid unnecessary workload.</li>
150</ul>
151</p>
152
153<p>
154The main window of BNC shows a 'Top menu bar' section, a 'Settings' sections with tabs to set processing options, a 'Streams' section, a section for 'Log' tabs, and a 'Bottom menu bar' section, see figure below.
155</p>
156<p><img src="IMG/screenshot09.png"/></p>
157<p><u>Figure 5:</u> Sections on BNC's main window.</p>
158
159<p>
160Running BNC in interactive mode requires graphics support. This is also
161required in batch mode when producing plots. Windows and Mac systems always
162support graphics. However, when using BNC in batch mode on Linux systems for
163producing plots, you need to make sure that at least a virtual X-Server like
164'Xvfb' is installed and the '-display' command-line option is used.
165</p>
166
167<p>
168The usual handling of BNC is that you first select a number of streams ('Add Stream'). Any stream configured to BNC shows up on the 'Streams' canvas in the middle of BNC's main window. You then go through BNC's various configuration tabs to select a combination of input, processing and output options before you start the program ('Start'). Most configuration tabs are dedicated to a certain functionality of BNC. If the first option field on such a configuration tab is empty, the affected functionality is - apart from a few exceptions - deactivated.</p>
169
170Records of BNC's activities are shown in the 'Log' tab. The bandwidth consumption per stream, the latency of incoming observations and a PPP time series for coordinates are shown in the 'Throughput', 'Latency' and 'PPP Plot' tabs of the main window.
171</p>
172<p>
173As a default, configuration files for running BNC on Unix/Linux/Mac systems are saved in directory '${HOME}/.config/BKG'. On Windows systems, they are typically saved in directory 'C:/Documents and Settings/Username/.config/BKG'. The default configuration file name is 'BNC.bnc'.</p>
174<p>
175The default file name 'BNC.bnc' can be changed and the file contents can easily be edited. On graphical user interfaces it is possible to Drag &amp; Drop a configuration file icon to start BNC (not on Mac systems). Some configuration options can be changed on-the-fly. See annexed 'Configuration Examples' for a complete set of configuration options. It is also possible to start and configure BNC via command line.
176</p>
177<p><a name="optsettings"><h3>3. Settings</h3></p>
178<p>
179This chapter describes how to set the BNC program options. It explains the top menu bar, the processing options, the 'Streams' and 'Log' sections, and the bottom menu bar.
180</p>
181<p>
182<b>Top Menu Bar</b><br>
1833.1. <a href=#topmenu>Top Menu Bar</a><br>
1843.1.1 <a href=#file>File</a><br>
1853.1.2 <a href=#help>Help</a><br><br>
186<b>Settings Canvas</b><br>
1873.2. <a href=#network>Network</a><br>
1883.2.1 <a href=#proxy>Proxy</a><br>
1893.2.2 <a href=#ssl>SSL</a><br>
1903.3. <a href=#general>General</a><br>
191&nbsp; &nbsp; &nbsp; 3.3.1. <a href=#genlog>Logfile</a><br>
192&nbsp; &nbsp; &nbsp; 3.3.2. <a href=#genapp>Append Files</a><br>
193&nbsp; &nbsp; &nbsp; 3.3.3. <a href=#genconf>Reread Configuration</a><br>
194&nbsp; &nbsp; &nbsp; 3.3.4. <a href=#genstart>Auto Start</a><br>
195&nbsp; &nbsp; &nbsp; 3.3.5. <a href=#rawout>Raw Output File</a><br>
1963.4. <a href=#rinex>RINEX Observations</a><br>
197&nbsp; &nbsp; &nbsp; 3.4.1. <a href=#rnxname>File Names</a><br>
198&nbsp; &nbsp; &nbsp; 3.4.2. <a href=#rnxdir>Directory</a><br>
199&nbsp; &nbsp; &nbsp; 3.4.3. <a href=#rnxinterval>File Interval</a><br>
200&nbsp; &nbsp; &nbsp; 3.4.4. <a href=#rnxsample>Sampling</a><br>
201&nbsp; &nbsp; &nbsp; 3.4.5. <a href=#rnxskl>Skeleton Extension</a><br>
202&nbsp; &nbsp; &nbsp; 3.4.6. <a href=#rnxscript>Script</a><br>
203&nbsp; &nbsp; &nbsp; 3.4.7. <a href=#rnxvers>Version</a><br>
2043.5. <a href=#ephemeris>RINEX Ephemeris</a><br>
205&nbsp; &nbsp; &nbsp; 3.5.1. <a href=#ephdir>Directory</a><br>
206&nbsp; &nbsp; &nbsp; 3.5.2. <a href=#ephint>Interval</a><br>
207&nbsp; &nbsp; &nbsp; 3.5.3. <a href=#ephport>Port</a><br>
208&nbsp; &nbsp; &nbsp; 3.5.4. <a href=#ephvers>Version</a><br>
2093.6. <a href=#reqc>RINEX Editing & QC</a><br>
210&nbsp; &nbsp; &nbsp; 3.6.1 <a href=#reqcact>Action</a><br>
211&nbsp; &nbsp; &nbsp; 3.6.2 <a href=#reqcedit>Set Edit Options</a><br>
212&nbsp; &nbsp; &nbsp; 3.6.3 <a href=#reqcinput>Input Files</a><br>
213&nbsp; &nbsp; &nbsp; 3.6.4 <a href=#reqcoutput>Output Files</a><br>
214&nbsp; &nbsp; &nbsp; 3.6.5 <a href=#reqcplots>Directory for Plots</a><br>
215&nbsp; &nbsp; &nbsp; 3.6.6 <a href=#reqccommand>Command Line, No Window</a><br>
2163.7. <a href=#correct>Broadcast Corrections</a><br>
217&nbsp; &nbsp; &nbsp; 3.7.1. <a href=#corrdir>Directory, ASCII</a><br>
218&nbsp; &nbsp; &nbsp; 3.7.2. <a href=#corrint>Interval</a><br>
219&nbsp; &nbsp; &nbsp; 3.7.3. <a href=#corrport>Port</a><br>
220&nbsp; &nbsp; &nbsp; 3.7.4. <a href=#corrwait>Wait for Full Corr Epoch</a><br>
2213.8. <a href=#syncout>Feed Engine</a><br>
222&nbsp; &nbsp; &nbsp; 3.8.1. <a href=#syncport>Port</a><br>
223&nbsp; &nbsp; &nbsp; 3.8.2. <a href=#syncwait>Wait for Full Obs Epoch</a><br>
224&nbsp; &nbsp; &nbsp; 3.8.3. <a href=#syncsample>Sampling</a><br>
225&nbsp; &nbsp; &nbsp; 3.8.4. <a href=#syncfile>File</a><br>
226&nbsp; &nbsp; &nbsp; 3.8.5. <a href=#syncuport>Port (unsynchronized)</a><br>
2273.9. <a href=#serial>Serial Output</a><br>
228&nbsp; &nbsp; &nbsp; 3.9.1. <a href=#sermount>Mountpoint</a><br>
229&nbsp; &nbsp; &nbsp; 3.9.2. <a href=#serport>Port Name</a><br>
230&nbsp; &nbsp; &nbsp; 3.9.3. <a href=#serbaud>Baud Rate</a><br>
231&nbsp; &nbsp; &nbsp; 3.9.4. <a href=#serflow>Flow Control</a><br>
232&nbsp; &nbsp; &nbsp; 3.9.5. <a href=#serparity>Parity</a><br>
233&nbsp; &nbsp; &nbsp; 3.9.6. <a href=#serdata>Data Bits</a><br>
234&nbsp; &nbsp; &nbsp; 3.9.7. <a href=#serstop>Stop Bits</a><br>
235&nbsp; &nbsp; &nbsp; 3.9.8. <a href=#serauto>NMEA</a><br>
236&nbsp; &nbsp; &nbsp; 3.9.9. <a href=#serfile>File</a><br>
237&nbsp; &nbsp; &nbsp; 3.9.10. <a href=#serheight>Height</a><br>
2383.10. <a href=#advnote>Outages</a><br>
239&nbsp; &nbsp; &nbsp; 3.10.1. <a href=#obsrate>Observation Rate</a><br>
240&nbsp; &nbsp; &nbsp; 3.10.2. <a href=#advfail>Failure Threshold</a><br>
241&nbsp; &nbsp; &nbsp; 3.10.3. <a href=#advreco>Recovery Threshold</a><br>
242&nbsp; &nbsp; &nbsp; 3.10.4. <a href=#advscript>Script</a><br>
2433.11. <a href=#misc>Miscellaneous</a><br>
244&nbsp; &nbsp; &nbsp; 3.11.1. <a href=#miscmount>Mountpoint</a><br>
245&nbsp; &nbsp; &nbsp; 3.11.2. <a href=#miscperf>Log Latency</a><br>
246&nbsp; &nbsp; &nbsp; 3.11.3. <a href=#miscscan>Scan RTCM</a><br>
2473.12. <a href=#pppclient>PPP Client</a><br>
248&nbsp; &nbsp; &nbsp; 3.12.1 <a href=#pppmode>Mode & Mountpoints</a><br>
249&nbsp; &nbsp; &nbsp; 3.12.1.1 <a href=#pppmodus>Mode</a><br>
250&nbsp; &nbsp; &nbsp; 3.12.1.2 <a href=#pppobsmount>Obs Mountpoint</a><br>
251&nbsp; &nbsp; &nbsp; 3.12.1.3 <a href=#pppcorrmount>Corr Mountpoint</a><br>
252&nbsp; &nbsp; &nbsp; 3.12.2 <a href=#pppxyz>Marker Coordinates</a><br>
253&nbsp; &nbsp; &nbsp; 3.11.3 <a href=#pppneu>Antenna Eccentricity</a><br>
254&nbsp; &nbsp; &nbsp; 3.12.4 <a href=#pppoutput>NMEA & Plot Output</a><br>
255&nbsp; &nbsp; &nbsp; 3.12.4.1 <a href=#pppnmeafile>NMEA File</a><br>
256&nbsp; &nbsp; &nbsp; 3.12.4.2 <a href=#pppnmeaport>NMEA Port</a><br>
257&nbsp; &nbsp; &nbsp; 3.12.4.3 <a href=#pppplot>PPP Plot</a><br>
258&nbsp; &nbsp; &nbsp; 3.12.5 <a href=#ppppost>Post Processing</a><br>
259&nbsp; &nbsp; &nbsp; 3.12.6 <a href=#ppprecant>Antennas</a><br>
260&nbsp; &nbsp; &nbsp; 3.12.6.1 <a href=#pppantex>ANTEX File</a><br>
261&nbsp; &nbsp; &nbsp; 3.12.6.2 <a href=#ppprecantenna>Antenna Name</a><br>
262&nbsp; &nbsp; &nbsp; 3.12.7 <a href=#pppbasics>Basics</a><br>
263&nbsp; &nbsp; &nbsp; 3.12.7.1 <a href=#pppphase>Use Phase Obs</a><br>
264&nbsp; &nbsp; &nbsp; 3.12.7.2 <a href=#ppptropo>Estimate Tropo</a><br>
265&nbsp; &nbsp; &nbsp; 3.12.7.3 <a href=#pppglo>Use GLONASS</a><br>
266&nbsp; &nbsp; &nbsp; 3.12.7.4 <a href=#pppgal>Use Galileo</a><br>
267&nbsp; &nbsp; &nbsp; 3.12.7.5 <a href=#pppsync>Sync Corr</a><br>
268&nbsp; &nbsp; &nbsp; 3.12.7.6 <a href=#pppaverage>Averaging</a><br>
269&nbsp; &nbsp; &nbsp; 3.12.7.7 <a href=#pppquick>Quick-Start</a><br>
270&nbsp; &nbsp; &nbsp; 3.12.7.8 <a href=#pppgap>Maximal Solution Gap</a><br>
271&nbsp; &nbsp; &nbsp; 3.12.8 <a href=#pppsigmas>Sigmas</a><br>
272&nbsp; &nbsp; &nbsp; 3.12.8.1 <a href=#pppsigc>Code</a><br>
273&nbsp; &nbsp; &nbsp; 3.12.8.2 <a href=#pppsigp>Phase</a><br>
274&nbsp; &nbsp; &nbsp; 3.12.8.3 <a href=#pppsigxyzi>XYZ Init</a><br>
275&nbsp; &nbsp; &nbsp; 3.12.8.4 <a href=#pppsigxyzn>XYZ White Noise</a><br>
276&nbsp; &nbsp; &nbsp; 3.12.8.5 <a href=#pppsigtrpi>Tropo Init</a><br>
277&nbsp; &nbsp; &nbsp; 3.12.8.6 <a href=#pppsigtrpn>Tropo White Noise</a><br>
2783.13. <a href=#combi>Combine Corrections</a><br>
279&nbsp; &nbsp; &nbsp; 3.13.1 <a href=#combimounttab>Combine Corrections Table</a><br>
280&nbsp; &nbsp; &nbsp; 3.13.1.1 <a href=#combiadd>Add Row, Delete</a><br>
281&nbsp; &nbsp; &nbsp; 3.13.1.2 <a href=#combimethod>Method</a><br>
282&nbsp; &nbsp; &nbsp; 3.13.1.3 <a href=#combimax>Maximal Residuum</a><br>
283&nbsp; &nbsp; &nbsp; 3.13.1.4 <a href=#combismpl>Sampling</a><br>
2843.14. <a href=#upclk>Upload Corrections</a><br>
285&nbsp; &nbsp; &nbsp; 3.14.1 <a href=#upadd>Add, Delete Row</a><br>
286&nbsp; &nbsp; &nbsp; 3.14.2 <a href=#uphost>Host, Port, Mountpoint, Password</a><br>
287&nbsp; &nbsp; &nbsp; 3.14.3 <a href=#upsystem>System</a><br>
288&nbsp; &nbsp; &nbsp; 3.14.4 <a href=#upcom>Center of Mass</a><br>
289&nbsp; &nbsp; &nbsp; 3.14.5 <a href=#upsp3>SP3 File</a><br>
290&nbsp; &nbsp; &nbsp; 3.14.6 <a href=#uprinex>RNX File</a><br>
291&nbsp; &nbsp; &nbsp; 3.14.7 <a href=#upinter>Interval</a><br>
292&nbsp; &nbsp; &nbsp; 3.14.8 <a href=#upclksmpl>Sampling</a><br>
293&nbsp; &nbsp; &nbsp; 3.14.8.1 <a href=#upclkorb>orbits</a><br>
294&nbsp; &nbsp; &nbsp; 3.14.8.2 <a href=#upclksp3>SP3</a><br>
295&nbsp; &nbsp; &nbsp; 3.14.8.3 <a href=#upclkrnx>RINEX </a><br>
296&nbsp; &nbsp; &nbsp; 3.14.9 <a href=#upcustom>Custom Trafo</a><br>
2973.15. <a href=#upeph>Upload Ephemeris</a><br>
298&nbsp; &nbsp; &nbsp; 3.15.1 <a href=#brdcserver>Host &amp; Port</a><br>
299&nbsp; &nbsp; &nbsp; 3.15.2 <a href=#brdcmount>Mountpoint &amp; Password</a><br>
300&nbsp; &nbsp; &nbsp; 3.15.3 <a href=#brdcsmpl>Sampling</a><br><br>
301<b>Streams Canvas</b><br>
3023.16. <a href=#streams>Streams</a><br>
303&nbsp; &nbsp; &nbsp; 3.16.1 <a href=#streamedit>Edit Streams</a><br>
304&nbsp; &nbsp; &nbsp; 3.16.2 <a href=#streamdelete>Delete Stream</a><br>
305&nbsp; &nbsp; &nbsp; 3.16.3 <a href=#streamconf>Reconfigure Stream Selection On-the-fly</a><br><br>
306<b>Logging Canvas</b><br>
3073.17. <a href=#logs>Logging</a><br>
308&nbsp; &nbsp; &nbsp; 3.17.1 <a href=#logfile>Log</a><br>
309&nbsp; &nbsp; &nbsp; 3.17.2 <a href=#throughput>Throughput</a><br>
310&nbsp; &nbsp; &nbsp; 3.17.3 <a href=#latency>Latency</a><br>
311&nbsp; &nbsp; &nbsp; 3.17.4 <a href=#ppptab>PPP Plot</a><br><br>
312<b>Bottom Menu Bar</b><br>
3133.18. <a href=#bottom>Bottom Menu Bar</a><br>
314&nbsp; &nbsp; &nbsp; 4.18.1. <a href=#streamadd>Add Stream - Coming from Caster</a><br>
315&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 3.18.1.1 <a href=#streamhost>Caster Host and Port</a><br>
316&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 3.18.1.2 <a href=#streamtable>Casters Table</a><br>
317&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 3.18.1.3 <a href=#streamuser>User and Password</a><br>
318&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 3.18.1.4 <a href=#gettable>Get Table</a><br>
319&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 3.18.1.5 <a href=#ntripv>NTRIP Version</a><br>
320&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 3.18.1.6 <a href=#map>Map</a><br>
321&nbsp; &nbsp; &nbsp; 3.18.2 <a href=#streamip>Add Stream - Coming from TCP/IP Port</a><br>
322&nbsp; &nbsp; &nbsp; 3.18.3 <a href=#streamudp>Add Stream - Coming from UDP Port</a><br>
323&nbsp; &nbsp; &nbsp; 3.18.4 <a href=#streamser>Add Stream - Coming from Serial Port</a><br>
324&nbsp; &nbsp; &nbsp; 3.18.5 <a href=#start>Start</a><br>
325&nbsp; &nbsp; &nbsp; 3.18.6 <a href=#stop>Stop</a><br><br>
326<b>Command Line</b><br>
3273.19. <a href=#cmd>Command Line Options</a><br>
328&nbsp; &nbsp; &nbsp; 3.19.1. <a href=#nw>No Window Mode</a><br>
329&nbsp; &nbsp; &nbsp; 3.19.2. <a href=#post>File Mode</a><br>
330&nbsp; &nbsp; &nbsp; 3.19.3. <a href=#conffile>Configuration File</a><br>
331&nbsp; &nbsp; &nbsp; 3.19.4. <a href=#confopt>Configuration Options</a><br>
332</p>
333
334<p><a name="topmenu"><h4>3.1. Top Menu Bar</h4></p>
335<p>
336The top menu bar allows selecting a font for the BNC windows, save configured options, or quit the program execution. It also provides access to program documentation.
337</p>
338
339<p><a name="file"><h4>3.1.1 File</h4></p>
340
341<p>
342The 'File' button lets you
343<ul>
344<li> select an appropriate font.<br>
345Use smaller font size if the BNC main window exceeds the size of your screen.
346</li>
347<li> save selected options in configuration file.<br>
348When using 'Save &amp; Reread Configuration' while BNC is already processing data, some configuration options become immediately effective on-the-fly without interrupting uninvolved threads. See annexed section 'Configuration Examples' for a list of on-the-fly changeable configuration options.
349</li>
350<li> quit the BNC program.
351</li>
352</ul>
353</p>
354
355<p><a name="help"><h4>3.1.2 Help</h4></p>
356
357<p>
358The 'Help' button provides access to
359<ul>
360<li>
361help contents.<br>
362You may keep the 'Help Contents' window open while configuring BNC.
363</li>
364<li>
365a 'Flow Chart' showing BNC linked to a real-time GNSS network engine such as RTNet.
366</li>
367<li>
368general information about BNC.<br>
369Close the 'About BNC' window to continue working with BNC.
370</li>
371</ul>
372</p>
373<p>
374BNC comes with a help system providing online information about its functionality and usage. Short descriptions are available for any widget. Focus to the relevant widget and press Shift+F1 to request help information. A help text appears immediately; it disappears as soon as the user does something else. The dialogs on some operating systems may provide a &quot;?&quot; button that users can click; click the relevant widget to pop up the help text.
375</p>
376
377<p><a name="network"><h4>3.2. Network</h4></p>
378<p>
379You may need to specify a proxy when running BNC in a protected network. You may also like to use the Transport Layer Security (TLS) and its predecessor, Secure Sockets Layer (SSL) cryptographic protocols for secure NTRIP communication over the Internet.
380</p>
381<p><a name="proxy"><h4>3.2.1 Proxy - Usage in a protected LAN</h4></p>
382<p>
383If you are running BNC within a protected Local Area Network (LAN), you might need to use a proxy server to access the Internet. Enter your proxy server IP and port number in case one is operated in front of BNC. If you don't know the IP and port of your proxy server, check the proxy server settings in your Internet browser or ask your network administrator.</p>
384<p>
385Note that IP streaming is often not allowed in a LAN. In this case you need to ask your network administrator for an appropriate modification of the local security policy or for the installation of a TCP relay to the NTRIP Broadcasters. If these are not possible, you might need to run BNC outside your LAN on a host that has unobstructed connection to the Internet.
386</p>
387
388<p><a name="ssl"><h4>3.2.2 SSL - Transport Layer Security</h4></p>
389<p>Communication with an NTRIP Broadcaster over SSL requires the exchange of client and/or server certificates. Specify the path to a directory where you save certificates on your system. You may like to check out <u>http://software.rtcm-ntrip.org/wiki/Certificates</u> for a list of known NTRIP Server certificates. You may also just try communication via SSL to check out whether this is supported by the involved NTRIP Broadcaster. </p>
390<p>SSL communication may involve queries coming from the NTRIP Broadcaster. Tick 'Ignore SSL authorization errors' if you don't want to be bothered with this. Note that SSL communication is usually done over port 443.</p>
391
392<p><a name="general"><h4>3.3. General</h4></p>
393<p>
394The following defines general settings for BNC's logfile, file handling, reconfiguration on-the-fly, and auto-start.
395</p>
396
397<p><a name="genlog"><h4>3.3.1 Logfile - optional</h4></p>
398<p>
399Records of BNC's activities are shown in the 'Log' tab on the bottom of the main window. These logs can be saved into a file when a valid path is specified in the 'Logfile (full path)' field. The logfile name will automatically be extended by a string '_YYMMDD' carrying the current date. This leads to series of daily logfiles when running BNC continuously for extended. Message logs cover the communication status between BNC and the NTRIP Broadcaster as well as problems that may occur in the communication link, stream availability, stream delay, stream conversion etc. All times are given in UTC. The default value for 'Logfile (full path)' is an empty option field, meaning that BNC logs will not be saved into a file.
400</p>
401
402<p><a name="genapp"><h4>3.3.2 Append Files - optional</h4></p>
403<p>
404When BNC is started, new files are created by default and any existing files with the same name will be overwritten. However, users might want to append existing files following a restart of BNC, a system crash or when BNC crashed. Tick 'Append files' to continue with existing files and keep what has been recorded so far. Note that option 'Append files' affects all types of files created by BNC.
405</p>
406
407<p><a name="genconf"><h4>3.3.3 Reread Configuration - optional</h4></p>
408<p>
409When operating BNC online in 'no window' mode (command line option -nw), some configuration options can nevertheless be changed on-the-fly without interrupting the running process. For that you force the program to reread parts of its configuration in pre-defined intervals from the disk. Select '1 min', '1 hour', or '1 day' to let BNC reread on-the-fly changeable configuration options every full minute, hour, or day. This lets in between edited options become effective without interrupting uninvolved threads. See annexed section 'Configuration Examples' for a configuration file example and a list of on-the-fly changeable options.
410</p>
411
412<p><a name="genstart"><h4>3.3.4 Auto Start - optional</h4></p>
413<p>
414You may like to auto-start BNC at startup time in window mode with pre-assigned configuration options. This may be required i.e. immediately after booting your system. Tick 'Auto start' to supersede the usage of the 'Start' button. Make sure that you maintain a link to BNC for that in your Autostart directory (Windows systems) or call BNC in a script below directory /etc/init.d (Unix/Linux/Mac systems).
415</p>
416<p>
417 See BNC's command line option -nw for an auto-start of BNC in 'no window' mode.
418</p>
419
420<p><a name="rawout"><h4>3.3.5 Raw Output File - optional</h4></p>
421<p>
422BNC can save all data coming in through various streams in one daily file. The information is recorded in the specified 'Raw output file' in the received order and format. This feature allows a BNC user to run the PPP option offline with observations, Broadcast Corrections, and Broadcast Ephemeris being read from a previously saved file. It supports the offline repetition of a real-time situation for debugging purposes and it is not meant for Post Processing.
423</p>
424<p>
425Data will be saved in blocks in the received format separated by ASCII time stamps like (example):
426<pre>
4272010-08-03T18:05:28 RTCM3EPH RTCM_3 67
428</pre>
429</p>
430<p>
431This example block header tells you that 67 bytes were saved in the data block following this time stamp. The information in this block is encoded in RTCM Version 3 format, comes from mountpoint RTCM3EPH and was received at 18:05:29 UTC on 2010-08-03. BNC adds its own time stamps in order to allow the reconstruction of a recorded real-time situation.
432</p>
433<p>
434The default value for 'Raw output file' is an empty option field, meaning that BNC will not save all raw data into one single daily file.
435</p>
436
437<p><a name="rinex"><h4>3.4. RINEX Observations</h4></p>
438<p>
439Observations will be converted to RINEX if they come in either RTCM Version 2 or RTCM Version 3 format. Depending on the RINEX version and incoming RTCM message types, files generated by BNC may contain data from GPS, GLONASS, Galileo, SBAS, QZSS and COMPASS. In case an observation type is listed in the RINEX header but the corresponding observation is unavailable, its value is set to zero '0.000'. Note that the 'RINEX TYPE' field in the RINEX Version 3 Observation file header is always set to 'M(MIXED)' or 'Mixed' even if the file only contains data from one system.
440</p>
441<p>
442It is important to understand that converting RTCM streams to RINEX files requires a-priori information on observation types for specifying a complete RINEX header. Regarding the RINEX Version 2 file header, BNC simply introduces all observation types defined in the Version 2 standard and later reports "0.000" for all observations which are not received. However, following this approach is not possible for RINEX Version 3 files from RTCM Version 3 MSM streams because of the huge number of observation types which might in principle show up. The solution implemented in BNC is to start with RINEX Version 3 observation type records from skeleton files (see section 'Skeleton Extension') and switch to a default selection of observation types when such skeleton file is not available or it does not contain the required information. The 'Default selection of observation types specified' for a RINEX Version 3 file would be as follows:
443</p>
444<pre>
445C 12 C2 L2 D2 S2 C6 L6 D6 S6 C7 L7 D7 S7 SYS / # / OBS TYPES
446E 20 C1 L1 D1 S1 C5 L5 D5 S5 C6 L6 D6 S6 C7 SYS / # / OBS TYPES
447 L7 D7 S7 C8 L8 D8 S8 SYS / # / OBS TYPES
448G 20 C1C L1C D1C S1C C1P L1P D1P S1P C2C L2C D2C S2C C2P SYS / # / OBS TYPES
449 L2P D2P S2P C5 D5 L5 S5 SYS / # / OBS TYPES
450J 16 C1 L1 D1 S1 C2 L2 D2 S2 C5 L5 D5 S5 C6 SYS / # / OBS TYPES
451 D6 L6 S6 SYS / # / OBS TYPES
452R 16 C1C L1C D1C S1C C1P L1P D1P S1P C2C L2C D2C S2C C2P SYS / # / OBS TYPES
453 L2P D2P S2P SYS / # / OBS TYPES
454S 8 C1 L1 D1 S1 C5 L5 D5 S5 SYS / # / OBS TYPES
455</pre>
456
457<p>
458The screenshot below shows an example setup of BNC when converting streams to RINEX. Streams are coming from various NTRIP Broadcasters as well as from a serial communication link. Specifying a decoder string 'ZERO' means to not convert the affected stream contents but save its contents as received.
459</p>
460<p><img src="IMG/screenshot16.png"/></p>
461<p><u>Figure 6:</u> BNC translating incoming streams to 15 min RINEX Version 3 files.</p>
462
463
464<p><a name="rnxname"><h4>3.4.1 RINEX File Names</h4></p>
465<p>
466RINEX file names are derived by BNC from the first 4 characters of the corresponding stream's mountpoint (4Char Station ID). For example, data from mountpoints FRANKFURT and WETTZELL will have hourly RINEX Observation files named</p>
467<p>
468FRAN{ddd}{h}.{yy}O<br>
469WETT{ddd}{h}.{yy}O
470</p>
471<p>
472where 'ddd' is the day of year, 'h' is a letter which corresponds to an hour long UTC time block and 'yy' is the year.
473</p>
474<p>
475If there is more than one stream with identical 4Char Station ID (same first 4 characters for their mountpoints), the mountpoint strings are split into two sub-strings and both become part of the RINEX file name. For example, when simultaneously retrieving data from mountpoints FRANKFURT and FRANCE, their hourly RINEX Observation files are named as</p>
476<p>
477FRAN{ddd}{h}_KFURT.{yy}O<br>
478FRAN{ddd}{h}_CE.{yy}O.
479</p>
480<p>
481If several streams show exactly the same mountpoint name (example: BRUS0 from <u>www.euref-ip.net</u> and BRUS0 from <u>www.igs-ip.net</u>), BNC adds an integer number to the file name leading i.e. to hourly RINEX Observation files like</p>
482<p>
483BRUS{ddd}{h}_0.{yy}O<br>
484BRUS{ddd}{h}_1.{yy}O.
485</p>
486<p>
487Note that RINEX file names for all intervals less than 1 hour follow the file name convention for 15 minutes RINEX Observation files i.e.</p>
488<p>
489FRAN{ddd}{h}{mm}.{yy}O
490</p>
491<p>
492where 'mm' is the starting minute within the hour.
493</p>
494
495<p><a name="rnxdir"><h4>3.4.2 Directory - optional</h4></p>
496<p>
497Here you can specify the path to where the RINEX Observation files will be stored. If the specified directory does not exist, BNC will not create RINEX Observation files. Default value for 'Directory' is an empty option field, meaning that no RINEX Observation files will be written.
498</p>
499
500<p><a name="rnxinterval"><h4>3.4.3 File Interval - mandatory if 'Directory' is set</h4></p>
501<p>
502Select the length of the RINEX Observation file generated. The default value is 15 minutes.
503</p>
504
505<p><a name="rnxsample"><h4>3.4.4 Sampling - mandatory if 'Directory' is set </h4></p>
506<p>
507Select the RINEX Observation sampling interval in seconds. A value of zero '0' tells BNC to store all received epochs into RINEX. This is the default value.
508</p>
509
510<p><a name="rnxskl"><h4>3.4.5 Skeleton Extension - optional</h4></p>
511<p>
512Whenever BNC starts generating RINEX Observation files (and then once every day at midnight), it first tries to retrieve information needed for RINEX headers from so-called public RINEX header skeleton files which are derived from sitelogs. A HTTP link to a directory containing these skeleton files may be available through data field number 7 of the affected NET record in the source-table. See <u>http://www.epncb.oma.be:80/stations/log/skl/brus.skl</u> for an example of a public RINEX header skeleton file for the Brussels EPN station.
513</p>
514<p>
515However, sometimes public RINEX header skeleton files are not available, their contents is not up to date, or you need to put additional/optional records in the RINEX header. For that BNC allows using personal skeleton files that contain the header records you would like to include. You can derive a personal RINEX header skeleton file from the information given in an up to date sitelog. A file in the RINEX Observations 'Directory' with a 'Skeleton extension' suffix is interpreted by BNC as a personal RINEX header skeleton file for the corresponding stream.
516</p>
517<p>
518Examples for personal skeleton file name convention: RINEX Observation files for mountpoints WETTZELL, FRANKFURT and FRANCE (same 4Char Station ID), BRUS0 from <u>www.euref-ip.net</u> and BRUS0 from <u>www.igs-ip.net</u> (same 4Char Station ID, identical mountpoint stings) would accept personal skeleton files named</p>
519<p>
520WETT.skl<br>
521FRAN_KFURT.skl<br>
522FRAN_CE.skl<br>
523BRUS_0.skl<br>
524BRUS_1.skl</p>
525<p>
526if 'Skeleton extension' is set to 'skl'.
527</p>
528<p>
529Note the following regulations regarding personal RINEX header skeleton files:
530<ul>
531<li>If such a file exists in the 'RINEX directory', the corresponding public RINEX header skeleton file is ignored. The RINEX header is generated solely from the contents of the personal skeleton.</li>
532<li>Personal skeletons should contain a complete first header record of type
533<br>- &nbsp; RINEX VERSION / TYPE<br></li>
534<li>They should then contain an empty header record of type
535<br>- &nbsp; PGM / RUN BY / DATE<br>
536BNC will complete this line and include it in the RINEX file header.</li>
537<li>They should further contain complete header records of type
538<br>- &nbsp; MARKER NAME
539<br>- &nbsp; OBSERVER / AGENCY
540<br>- &nbsp; REC # / TYPE / VERS
541<br>- &nbsp; ANT # / TYPE
542<br>- &nbsp; APPROX POSITION XYZ
543<br>- &nbsp; ANTENNA: DELTA H/E/N
544<br>- &nbsp; WAVELENGTH FACT L1/2 (RINEX Version 2)</li>
545<br>- &nbsp; SYS / # / OBS TYPES (RINEX Version 3, will be ignored when writing Version 2 files)</li>
546<li>They may contain any other optional complete header record as defined in the RINEX documentation.</li>
547<li>They should then contain empty header records of type
548<br>- &nbsp; # / TYPES OF OBSERV (RINEX Version 2, will be ignored when writing Version 3 files)
549<br>- &nbsp; TIME OF FIRST OBS
550<br>BNC will include these lines in the final RINEX file header together with an additional
551<br>- &nbsp; COMMENT
552<br>line describing the source of the stream.</li>
553<li>They should finally contain an empty header record of type
554<br>- &nbsp; END OF HEADER (last record)</li>
555</ul>
556<p>
557If neither a public nor a personal RINEX header skeleton file is available for BNC, a default header will be used.
558</p>
559<p>
560The following is a skeleton example for a RINEX file:
561</p>
562<p>
563<pre>
564 OBSERVATION DATA M (Mixed) RINEX VERSION / TYPE
565DUND MARKER NAME
56650212M003 MARKER NUMBER
5674635120796 TRIMBLE NETR9 1.15 REC # / TYPE / VERS
56812626150 TRM41249.00 NONE ANT # / TYPE
569 -4388121.1700 726671.0500 -4556535.6300 APPROX POSITION XYZ
570 0.0020 0.0000 0.0000 ANTENNA: DELTA H/E/N
571GeoNet Reception GNS OBSERVER / AGENCY
572G 28 21C L1C D1C S1C C1W L1W D1W S1W C5X L5X D5X S5X C2W SYS / # / OBS TYPES
573 L2W D2W S2W C2X L2X D2X S2X SYS / # / OBS TYPES
574R 16 C1C L1C D1C S1C C1P L1P D1P S1P C2P L2P D2P S2P C2C SYS / # / OBS TYPES
575 L2C D2C S2C SYS / # / OBS TYPES
576S 12 C1C L1C D1C S1C C1W L1W D1W S1W C5I L5I D5I S5I SYS / # / OBS TYPES
577E 8 C1 L1 D1 S1 C5 L5 D5 S5 SYS / # / OBS TYPES
578C 4 C2I L2I D2I S2I SYS / # / OBS TYPES
579J 12 C1C L1C D1C S1C C2 L2 D2 S2 C5 L5 D5 S5 SYS / # / OBS TYPES
580PORTIONS OF THIS HEADER GENERATED BY BKG FROM COMMENT
581SITELOG dund_20070806.log COMMENT
582</pre>
583<p>
584
585<p><a name="rnxscript"><h4>3.4.6 Script - optional</h4></p>
586<p>
587Whenever a RINEX Observation file is saved, you might want to compress copy or upload it immediately via FTP. BNC allows you to execute a script/batch file to carry out these operations. To do that, specify the full path of the script/batch file here. BNC will pass the RINEX Observation file path to the script as a command line parameter (%1 on Windows systems, $1 on Unix/Linux/Mac systems).
588</p>
589<p>
590The triggering event for calling the script or batch file is the end of a RINEX Observation file 'Interval'. If that is overridden by a stream outage, the triggering event is the stream reconnection.
591</p>
592<p>
593As an alternative to initiating file uploads through BNC, you may like to call an upload script or batch file through your crontable or Task Scheduler (independent from BNC) once every one or two minutes after the end of each RINEX file 'Interval'.
594</p>
595
596<p><a name="rnxvers"><h4>3.4.7 Version - optional</h4></p>
597<p>
598The default format for RINEX Observation files is RINEX Version 2.11. Select 'Version 3' if you would like to save observations in RINEX Version 3 format.
599</p>
600
601<p><a name="ephemeris"><h4>3.5. RINEX Ephemeris</h4></p>
602<p>
603Broadcast Ephemeris can be saved as RINEX Navigation files when received via RTCM Version 3 e.g. as message types 1019 (GPS) or 1020 (GLONASS) or 1045 (Galileo). The file name convention follows the details given in section 'RINEX File Names' except that the first four characters are 'BRDC' and the last character is
604</p>
605<ul>
606<li>'N' or 'G' for GPS or GLONASS ephemeris in two separate RINEX Version 2.11 Navigation files, or</li>
607<li>'P' for GPS plus GLONASS plus Galileo ephemeris saved together in one RINEX Version 3 Navigation file.
608</ul>
609
610<p>
611Note that streams dedicated to carry Broadcast Ephemeris messages in RTCM Version 3 format in high repetition rates are listed on <u>http://igs.bkg.bund.de/ntrip/ephemeris</u>.
612</p>
613
614<p><a name="ephdir"><h4>3.5.1 Directory - optional</h4></p>
615<p>
616Specify a path for saving Broadcast Ephemeris data as RINEX Navigation files. If the specified directory does not exist, BNC will not create RINEX Navigation files. Default value for Ephemeris 'Directory' is an empty option field, meaning that no RINEX Navigation files will be created.
617</p>
618
619<p><a name="ephint"><h4>3.5.2 Interval - mandatory if 'Directory' is set</h4></p>
620<p>
621Select the length of the RINEX Navigation file generated. The default value is 1 day.
622</p>
623
624<p><a name="ephport"><h4>3.5.3 Port - optional</h4></p>
625<p>
626BNC can output Broadcast Ephemeris in RINEX Version 3 format on your local host (IP 127.0.0.1) through an IP 'Port'. Specify an IP port number to activate this function. The default is an empty option field, meaning that no ASCII ephemeris output via IP port is generated.
627</p>
628<p>
629The source code for BNC comes with an example perl script 'test_tcpip_client.pl' that allows you to read BNC's ASCII ephemeris output from the IP port.
630</p>
631
632<p><a name="ephvers"><h4>3.5.4 Version - optional</h4></p>
633<p>
634Default format for RINEX Navigation files containing Broadcast Ephemeris is RINEX Version 2.11. Select 'Version 3' if you want to save the ephemeris in RINEX Version 3 format.
635</p>
636<p>
637Note that this does not concern the Broadcast Ephemeris output through IP port which is always in RINEX Version 3 format.
638</p>
639
640<p><a name="reqc"><h4>3.6. RINEX Editing & QC</h4></p>
641<p>
642Besides stream conversion from RTCM to RINEX, BNC allows editing RINEX files or concatenate their contents. RINEX Observation and Navigation files can be handled. BNC can also carry out a RINEX file quality check. In summary this functionality in BNC covers
643<ul>
644<li>Stream <u>T</u>ranslation</li>
645<li>File <u>E</u>diting and concatenation</li>
646<li>File <u>Q</b></u>uality <u>C</u>heck</li>
647</ul>
648and hence follows UNAVCO's famous 'TEQC' program. The remarkable thing about BNC in this context is that it supports RINEX Version 3 under GNU General Public License.
649
650<p><a name="reqcact"><h4>3.6.1 Action - optional</h4></p>
651<p>Select an action. Options are 'Edit/Concatenate' and 'Analyze'.
652<ul>
653<li>Select 'Edit/Concatenate' if you want to edit RINEX file contents according to options specified under 'Set Edit Options' or if you want to concatenate several RINEX files.</li>
654<li>Select 'Analyze' if you are interested in a quality check of your RINEX file contents.</li>
655</ul>
656</p>
657
658<p><a name="reqcedit"><h4>3.6.2 Set Edit Options - mandatory if 'Edit/Concatenate' is set</h4></p>
659<p>Once the 'Edit/Concatenate' action is selected, you have to 'Set Edit Options'. BNC lets you specify the RINEX version, sampling interval, begin and end of file, operator, comment lines, and marker, antenna, receiver details. Note that sampling, begin/end and marker/antenna/receiver specification are only meaningful for RINEX Observation files.
660</p>
661<p>
662When converting RINEX Version 2 to RINEX Version 3 Observation files, the tracking mode or channel information in the (last character out of the three characters) observation code is left blank if unknown. When converting RINEX Version 3 to RINEX Version 2 Observation files:
663<ul>
664<li>C1P in RINEX Version 3 is mapped to P1 in RINEX Version 2</li>
665<li>C2P in RINEX Version 3 is mapped to P2 in RINEX Version 2</li>
666<li>If several observations in RINEX Version 3 come with the same observation type and same band/frequency but different tracking modes, BNC uses only the one provided first for creating RINEX Version 2 while ignoring others.</li>
667</ul>
668</p>
669<p>Optionally you may specify a comment line text to be added to the emerging new RINEX file header. Any introduction of a newline through '\n' in this enforces the beginning of a further comment line. Comment line(s) will be added to the header immediately after the 'PGM / RUN BY / DATE' record. Default is an empty option field, meaning that no additional comment line will be added to the RINEX header.</p>
670 <p>Specifying a 'RUN BY' string to be included in the emerging new RINEX file header is another option. Default is an empty option field meaning the operator's ID is automatically used as 'RUN BY' string.</p>
671<p>
672If you specify a 'New' but no 'Old' marker/antenna/receiver name, the corresponding data field in the emerging new RINEX Observation file will be filled accordingly. If you in addition specify an 'Old' marker/antenna/receiver name, the corresponding data field in the emerging new RINEX Observation file will only be filled accordingly where 'Old' specifications match existing file contents.
673</p>
674
675<p><img src="IMG/screenshot27.png"/></p>
676<p><u>Figure 7:</u> Example for 'RINEX Editing Options' window.</p>
677
678<p><a name="reqcinput"><h4>3.6.3 Input Files - mandatory if 'Action' is set</h4></p>
679<p>
680Specify full path to input RINEX Observation file(s), and<br>
681specify full path to input RINEX Navigation file(s).
682</p>
683<p>When specifying several input files BNC will concatenate their contents.</p>
684
685<p><a name="reqcoutput"><h4>3.6.4 Output Files - mandatory if 'Action' is set</h4></p>
686<p>
687If 'Edit/Concatenate' is selected, specifying the a path to output RINEX Observation file(s) and specifying a full path to output RINEX Navigation file(s) is mandatory.</p>
688
689<p><img src="IMG/screenshot25.png"/></p>
690<p><u>Figure 8:</u> Example for RINEX file editing with BNC in Post Processing mode.</p>
691
692<p>
693If 'Analyze' is selected, specifying a 'Log' file to output analysis results is mandatory.<br>
694</p>
695
696<p><img src="IMG/screenshot29.png"/></p>
697<p><u>Figure 9:</u> Example for RINEX quality check output with BNC in Post Processing mode. A multipath analysis is presented in terms of a sky plot.</p>
698
699<p><a name="reqcplots"><h4>3.6.5 Directory for Plots - optional if 'Action' is set</h4></p>
700<p>
701If 'Analyze' is selected, specifying the path to a directory where plot files will be saved is optional. File names will be composed from the RINEX input file name(s) plus suffix 'PNG' to indicate the plot file format in use. </p>
702
703<p><a name="reqccommand"><h4>3.6.6 Command Line, No Window - optional</h4></p>
704<p>
705BNC applies options from the configuration file but allows updating every one of them on the command line while the contents of the configuration file remains unchanged, see section on 'Command Line Options'. The syntax for that looks as follows
706</p>
707<p>
708--key &lt;keyName&gt; &lt;keyValue&gt;
709</p>
710<p>
711where &lt;keyName&gt; stands for the name of an option contained in the configuration file and &lt;keyValue&gt; stands for the value you want to assign to it. This functionality may be helpful in the 'RINEX Editing & QC' context when running BNC on a routine basis for maintaining a RINEX file archive.
712</p>
713The following example for a Linux platform calls BNC in 'no window' mode with a local configuration file 'rnx.conf' for concatenating four 15min RINEX files residing in the local directory to produce an hourly RINEX Version 3 file with 30 seconds sampling interval:
714</p>
715<p>
716./bnc --nw --conf rnx.conf --key reqcAction Edit/Concatenate --key reqcObsFile "tlse119b00.12o,tlse119b15.12o,tlse119b30.12o,tlse119b45.12o" --key reqcOutObsFile tlse119b.12o --key reqcRnxVersion 3 --key reqcSampling 30
717</p>
718<p>
719You may use asterisk '*' and/or question mark '?' wildcard characters as shown with the following globbing command line option to specify a selection of files in a local directory:
720</p>
721<p>
722--key reqcObsFile "tlse*"<br>
723or:<br>
724--key reqcObsFile tlse\*
725</p>
726
727<p>The following Linux command line produces RINEX QC multipath plots offline in 'no window' mode and saves them in directory '/home/user'. Introducing a dummy configuration file /dev/null makes sure that no configuration options previously saved on disc are used:</p>
728<p>
729/home/user/bnc --conf /dev/null --key reqcAction Analyze --key reqcObsFile CUT02070.12O --key reqcNavFile BRDC2070.12P --key reqcOutLogFile CUT0.txt --key reqcPlotDir /home/user --nw
730</p>
731<p></p>
732<p>The following Linux command line produces the same RINEX QC multipath plots in interactive autoStart mode:</p>
733<p>
734/home/user/bnc --conf /dev/null --key reqcAction Analyze --key reqcObsFile CUT02070.12O --key reqcNavFile BRDC2070.12P --key reqcOutLogFile CUT0.txt --key --key startTab 4 --key autoStart 2
735</p>
736
737<p>
738The following is a list of available keynames for '<u>R</u>INEX <u>E</u>diting & <u>QC</u>' (short: REQC, pronounced 'rek') options and their meaning, cf. section 'Configuration Examples':
739</p>
740
741<table>
742<tr></tr>
743<tr><td><b>Keyname</b></td><td><b>Meaning</b></td></tr>
744<tr><td>reqcAction</td><td>RINEX Editing & QC action</td></tr>
745<tr><td>reqcObsFile</td><td>RINEX Observation input file(s)</td></tr>
746<tr><td>reqcNavFile</td><td>RINEX Navigation input files(s)</td></tr>
747<tr><td>reqcOutObsFile</td><td>RINEX Observation output file</td></tr>
748<tr><td>reqcPlotDir</td><td>RINEX QC multipath plot directory</td></tr>
749<tr><td>reqcOutNavFile</td><td>RINEX Navigation output file</td></tr>
750<tr><td>reqcOutLogFile</td><td>Logfile</td></tr>
751<tr><td>reqcRnxVersion</td><td>RINEX version of emerging new file</td></tr>
752<tr><td>reqcSampling</td><td>Sampling interval of emerging new RINEX file</td></tr>
753<tr><td>reqcStartDateTime</td><td>Begin of emerging new RINEX file</td></tr>
754<tr><td>reqcEndDateTime</td><td>End of emerging new RINEX file</td></tr>
755<tr><td>reqcRunBy</td><td>Operator name</td></tr>
756<tr><td>reqcComment</td><td>Additional comment lines</td></tr>
757<tr><td>reqcOldMarkerName</td><td>Old marker name</td></tr>
758<tr><td>reqcNewMarkerName</td><td>New marker name</td></tr>
759<tr><td>reqcOldAntennaName</td><td>Old antenna name</td></tr>
760<tr><td>reqcNewAntennaName</td><td>New antenna name</td></tr>
761<tr><td>reqcOldReceiverName</td><td>Old receiver name</td></tr>
762<tr><td>reqcNewReceiverName</td><td>New receiver name</td></tr>
763</table>
764
765<p><a name="correct"><h4>3.7. Broadcast Corrections</h4></p>
766<p>
767Differential GNSS and RTK operation using RTCM streams is currently based on corrections and/or raw measurements from single or multiple reference stations. This approach to differential positioning is using 'observation space' information. The representation with the RTCM standard can be called 'ObservationSpace Representation' (OSR).
768</p>
769<p>
770An alternative to the observation space approach is the so called 'sate space' approach. The principle here is to provide information on individual error sources. It can be called 'State Space Representation' (SSR). For a rover position, state space information concerning precise satellite clocks, orbits, ionosphere, troposphere et cetera can be converted into observation space and used to correct the rover observables for more accurate positioning. Alternatively the state information can directly be used in the rover's processing or adjustment model.
771</p>
772<p>
773RTCM has developed Version 3 messages to transport satellite clock and orbit corrections in real-time. The current set of SSR messages concerns:
774<ul>
775<li>Orbit corrections to Broadcast Ephemeris</li>
776<li>Clock corrections to Broadcast Ephemeris</li>
777<li>Code biases</li>
778<li>Combined orbit and clock corrections to Broadcast Ephemeris</li>
779<li>User Range Accuracy (URA)</li>
780<li>High-rate GPS clock corrections to Broadcast Ephemeris</li>
781</ul>
782<p>
783RTCM Version 3 streams carrying these messages may be used i.e. to support real-time Precise Point Positioning (PPP) applications.
784</p>
785<p>
786When using clocks from Broadcast Ephemeris (with or without applied corrections) or clocks from SP3 files, it may be important to understand that they are not corrected for the conventional periodic relativistic effect. Chapter 10 of the IERS Conventions 2003 mentions that the conventional periodic relativistic correction to the satellite clock (to be added to the broadcast clock) is computed as dt = -2 (R * V) / c^2 where R * V is the scalar product of the satellite position and velocity and c is the speed of light. This can also be found in the GPS Interface Specification, IS-GPS-200, Revision D, 7 March 2006.
787</p>
788
789<p>
790Orbit corrections are provided in along-track, cross-track and radial components. These components are defined in the Earth-centered, Earth-fixed reference frame of the broadcast ephemerides. For an observer in this frame, the along-track component is aligned in both direction and sign with the velocity vector, the cross-track component is perpendicular to the plane defined by the satellite position and velocity vectors, and the radial direction is perpendicular to the along track and cross-track ones. The three components form a right-handed orthogonal system.
791</p>
792
793<p>
794After applying corrections, the satellite position and clock is referred to the 'ionospheric free' phase center of the antenna which is compatible with the broadcast orbit reference.
795</p>
796
797<p>
798The orbit and clock corrections do not include local effects (like Ocean Loading or Solid Earth Tides) or atmospheric effects (Ionosphere and/or troposphere). Depending on the accuracy of your application you should correct for such effects by other means. There is currently no RTCM SSR message for ionospheric state parameters. Such messages are needed for accurate single frequency applications. The development of Iono messages will be the next step in the schedule of the RTCM State Space Representation Working Group.
799</p>
800
801<p>
802Broadcast Corrections can be saved by BNC in files. The file name convention for Broadcast Correction files follows the convention for RINEX files except for the last character of the file name suffix which is set to &quot;C&quot;.
803</p>
804
805<p>
806Saved files contain blocks of records in plain ASCII format where - separate for each GNSS, message type, stream, and epoch - the begin of a block is indicated by a line like (examples):
807</p>
808<p>
809! Orbits/Clocks: 30 GPS 0 Glonass CLK11<br>
810or<br>
811! Orbits/Clocks: 0 GPS 19 Glonass CLK11
812<p>
813Such line informs you about the number of records (here 30 and 19) carrying GPS or GLONASS related parameters you should receive next.
814</p>
815<p>
816The first five parameters in each Broadcast Corrections record are:
817</p>
818<p>
819<ul>
820<li>RTCM Version 3 message type number</li>
821<li>SSR message update interval indicator</li>
822<ul>
823<li>0 = 1 sec</li>
824<li>1 = 2 sec</li>
825<li>2 = 5 sec</li>
826<li>3 = 10 sec</li>
827<li>4 = 15 sec</li>
828<li>5 = 30 sec</li>
829<li>6 = 60 sec</li>
830<li>7 = 120 sec</li>
831<li>8 = 240 sec</li>
832<li>9 = 300 sec</li>
833<li>10 = 600 sec</li>
834<li>11 = 900 sec</li>
835<li>12 = 1800 sec</li>
836<li>13 = 3600 sec</li>
837<li>14 = 7200 sec</li>
838<li>15 = 10800 sec</li>
839</ul>
840<li>GPS Week</li>
841<li>Second in GPS Week</li>
842<li>GNSS Indicator and Satellite Vehicle Pseudo Random Number</li>
843</ul>
844</p>
845<p>
846In case of RTCM message types 1057 or 1063 (see Annex) these parameters are followed by
847</p>
848<p>
849<ul>
850<li>IOD referring to Broadcast Ephemeris set</li>
851<li>Radial Component of Orbit Correction to Broadcast Ephemeris [m]</li>
852<li>Along-track Component of Orbit Correction to Broadcast Ephemeris [m]</li>
853<li>Cross-track Component of Orbit Correction to Broadcast Ephemeris [m]</li>
854<li>Velocity of Radial Component of Orbit Correction to Broadcast Ephemeris [m/s]</li>
855<li>Velocity of Along-track Component of Orbit Correction to Broadcast Ephemeris [m/s]</li>
856<li>Velocity of Cross-track Component of Orbit Correction to Broadcast Ephemeris [m/s]</li>
857<p>
858</ul>
859</p>
860<p>
861Undefined parameters would be set to zero &quot;0.000&quot;.<br>Example:
862<pre>
863...
8641057 0 1686 283200.0 G02 21 1.062 -0.791 1.070 -0.00025 -0.00031 -0.00005
8651057 0 1686 283200.0 G03 25 1.765 -2.438 -0.290 -0.00009 -0.00060 0.00028
8661057 0 1686 283200.0 G04 14 1.311 -0.862 0.334 0.00005 -0.00038 -0.00015
867
868...
8691063 0 1686 283200.0 R01 39 0.347 1.976 -1.418 0.00048 -0.00091 0.00008
8701063 0 1686 283200.0 R02 39 0.624 -2.092 -0.155 0.00005 -0.00054 0.00053
8711063 0 1686 283200.0 R03 39 0.113 5.655 -1.540 0.00003 -0.00079 -0.00003
8721063 0 1686 283200.0 R05 39 0.237 1.426 -1.282 0.00054 -0.00020 0.00027
873...
874</pre>
875<p>
876In case of RTCM message types 1058 or 1064 (see Annex) the first five parameters in each record are followed by
877</p>
878<ul>
879<li>IOD set to zero &quot;0&quot;</li>
880<li>C0 polynomial coefficient for Clock Correction to Broadcast Ephemeris [m]</li>
881<li>C1 polynomial coefficient for Clock Correction to Broadcast Ephemeris [m/s]</li>
882<li>C2 polynomial coefficient for Clock Correction to Broadcast Ephemeris [m/s**2]</li>
883</ul>
884Example:
885</p>
886<pre>
887...
8881058 0 1538 211151.0 G18 0 1.846 0.000 0.000
8891058 0 1538 211151.0 G16 0 0.376 0.000 0.000
8901058 0 1538 211151.0 G22 0 2.727 0.000 0.000
891...
8921064 0 1538 211151.0 R08 0 8.956 0.000 0.000
8931064 0 1538 211151.0 R07 0 14.457 0.000 0.000
8941064 0 1538 211151.0 R23 0 6.436 0.000 0.000
895...
896</pre>
897</p>
898<p>
899In case of RTCM message types 1060 or 1066 (see Annex) the first five parameters in each record are followed by
900<p>
901<ul>
902<li>IOD referring to Broadcast Ephemeris set</li>
903<li>C0 polynomial coefficient for Clock Correction to Broadcast Ephemeris [m]</li>
904<li>Radial Component of Orbit Correction to Broadcast Ephemeris [m]</li>
905<li>Along-track Component of Orbit Correction to Broadcast Ephemeris [m]</li>
906<li>Cross-track Component of Orbit Correction to Broadcast Ephemeris [m]</li>
907<li>C1 polynomial coefficient for Clock Correction to Broadcast Ephemeris [m]</li>
908<li>Velocity of Radial Component of Orbit Correction to Broadcast Ephemeris [m/s]</li>
909<li>Velocity of Along-track Component of Orbit Correction to Broadcast Ephemeris [m/s]</li>
910<li>Velocity of Cross-track Component of Orbit Correction to Broadcast Ephemeris [m/s]</li>
911<li>C2 polynomial coefficient for Clock Correction to Broadcast Ephemeris [m]</li>
912</ul>
913Example:
914</p>
915<pre>
916...
9171060 0 1538 211610.0 G30 82 2.533 0.635 -0.359 -0.598 0.000 0.000 0.000 0.000 0.000
9181060 0 1538 211610.0 G31 5 -4.218 -0.208 0.022 0.002 0.000 0.000 0.000 0.000 0.000
9191060 0 1538 211610.0 G32 28 -2.326 0.977 -0.576 0.142 0.000 0.000 0.000 0.000 0.000
920...
9211066 0 1538 211610.0 R22 27 1.585 2.024 2.615 -2.080 0.000 0.000 0.000 0.000 0.000
9221066 0 1538 211610.0 R23 27 6.277 2.853 4.181 1.304 0.000 0.000 0.000 0.000 0.000
9231066 0 1538 211610.0 R24 27 0.846 1.805 13.095 6.102 0.000 0.000 0.000 0.000 0.000
924...
925</pre>
926</p>
927<p>
928In case of RTCM message types 1059 or 1065 (see Annex) the first five parameters in each record are followed by
929<ul>
930<li>Number of Code Biases</li>
931<li>Indicator to specify the signal and tracking mode</li>
932<li>Code Bias</li>
933<li>Indicator to specify the signal and tracking mode</li>
934<li>Code Bias</li>
935<li>etc.</li>
936</ul>
937Example:
938</p>
939<pre>
940...
9411059 0 1538 211151.0 G18 2 0 -0.010 11 -0.750
9421059 0 1538 211151.0 G16 2 0 -0.040 11 -0.430
9431059 0 1538 211151.0 G22 2 0 -0.630 11 -2.400
944...
945</pre>
946
947<p><a name="corrdir"><h4>3.7.1 Directory, ASCII - optional</h4></p>
948<p>
949Specify a directory for saving Broadcast Corrections in files. If the specified directory does not exist, BNC will not create Broadcast Correction files. Default value for Broadcast Corrections 'Directory' is an empty option field, meaning that no Broadcast Correction files will be created.
950</p>
951
952<p><a name="corrint"><h4>3.7.2 Interval - mandatory if 'Directory, ASCII' is set</h4></p>
953<p>
954Select the length of the Broadcast Correction files. The default value is 1 day.
955</p>
956
957<p><a name="corrport"><h4>3.7.3 Port - optional</h4></p>
958<p>
959BNC can output epoch by epoch synchronized Broadcast Corrections in ASCII format on your local host (IP 127.0.0.1) through an IP 'Port'. Specify an IP port number to activate this function. The default is an empty option field, meaning that no Broadcast Correction output via IP port is generated.
960</p>
961<p>
962The output format equals the format used for saving Broadcast Corrections in a file with the exception that the Mountpoint is added at each line's end.
963</p>
964<p>
965The following is an example output for streams from mountpoints RTCMSSR, CLK10 and CLK11:
966<pre>
967...
9681057 0 1538 211151.0 G18 1 0.034 0.011 -0.064 0.000 0.000 0.000 RTCMSSR
9691057 0 1538 211151.0 G16 33 -0.005 0.194 -0.091 0.000 0.000 0.000 RTCMSSR
9701057 0 1538 211151.0 G22 50 0.008 -0.082 -0.001 0.000 0.000 0.000 RTCMSSR
971...
9721058 0 1538 211151.0 G18 0 1.846 0.000 RTCMSSR
9731058 0 1538 211151.0 G16 0 0.376 0.000 RTCMSSR
9741058 0 1538 211151.0 G22 0 2.727 0.000 RTCMSSR
975...
9761059 0 1538 211151.0 G18 2 0 -0.010 11 -0.750 RTCMSSR
9771059 0 1538 211151.0 G16 2 0 -0.040 11 -0.430 RTCMSSR
9781059 0 1538 211151.0 G22 2 0 -0.630 11 -2.400 RTCMSSR
979...
9801063 0 1538 211151.0 R09 111 -0.011 -0.014 0.005 0.0000 0.000 0.000 RTCMSSR
9811063 0 1538 211151.0 R10 43 0.000 -0.009 -0.002 0.0000 0.000 0.000 RTCMSSR
9821063 0 1538 211151.0 R21 75 -0.029 0.108 0.107 0.0000 0.000 0.000 RTCMSSR
983...
9841064 0 1538 211151.0 R08 0 8.956 0.000 RTCMSSR
9851064 0 1538 211151.0 R07 0 14.457 0.000 RTCMSSR
9861064 0 1538 211151.0 R23 0 6.436 0.000 RTCMSSR
987...
9881066 0 1538 211610.0 R24 27 0.846 1.805 13.095 6.102 0.000 0.000 0.000 0.000 0.000 CLK11
9891066 0 1538 211610.0 R23 27 6.277 2.853 4.181 1.304 0.000 0.000 0.000 0.000 0.000 CLK11
9901066 0 1538 211610.0 R22 27 1.585 2.024 2.615 -2.080 0.000 0.000 0.000 0.000 0.000 CLK11
991...
9921060 0 1538 211610.0 G32 28 -2.326 0.977 -0.576 0.142 0.000 0.000 0.000 0.000 0.000 CLK10
9931060 0 1538 211610.0 G31 5 -4.218 -0.208 0.022 0.002 0.000 0.000 0.000 0.000 0.000 CLK10
9941060 0 1538 211610.0 G30 82 2.533 0.635 -0.359 -0.598 0.000 0.000 0.000 0.000 0.000 CLK10
995...
996</pre>
997</p>
998<p>
999The source code for BNC comes with an example perl script 'test_tcpip_client.pl' that allows you to read BNC's Broadcast Corrections from the IP port.
1000</p>
1001
1002<p><a name="corrwait"><h4>3.7.4 Wait for Full Corr Epoch - mandatory if 'Port' is set</h4></p>
1003<p>
1004When feeding a real-time GNSS network engine (see 'Feed Engine') waiting epoch by epoch for synchronized Broadcast Corrections, or when you 'Combine Corrections' BNC drops (only concerning IP port output) whatever is received later than 'Wait for full corr epoch' seconds. A value of 2 to 5 seconds could be an appropriate choice for that, depending on the latency of the incoming Broadcast Corrections stream and the delay acceptable by your application. A message such as &quot;COCK1: Correction overaged by 5 sec&quot; shows up in BNC's logfile if 'Wait for full corr epoch' is exceeded.
1005</p>
1006<p>
1007Specifying a value of '0' means that BNC immediately outputs all incoming Broadcast Ephemeris Corrections and does not drop any of them for latency reasons.
1008</p>
1009
1010<p><a name="syncout"><h4>3.8. Feed Engine</h4></p>
1011<p>
1012BNC can generate synchronized or unsynchronized observations epoch by epoch from all stations and satellites to feed a real-time GNSS network engine. Observations can be streamed out through an IP port and/or saved in a local file. The output is always in plain ASCII format and comprises the following parameters:
1013</p>
1014<p>
1015StationID | GPSWeek | GPSWeekSec | PRN, G=GPS, R=GLO | SlotNumber (if GLO) | Band/Frequency & trackingMode | Code | Phase | Doppler | SNR | SlipCount | ....
1016</p>
1017<p>
1018In case an observation is not available, its value is set to zero '0.000'.
1019</p>
1020<p>Note on 'SlipCount':<br>
1021It is the current understanding of BNC's authors that different slip counts could be referred to different phase measurements (i.e. L1C and L1P). The 'loss-of-lock' flags in RINEX are an example for making such kind of information available per phase measurement. However, it looks like we do have only one slip count in RTCM Version 3 for all phase measurements. As it could be that a receiver generates different slip counts for different phase measurements, we output one slip count per phase measurement to a listening real-time GNSS network engine.
1022</p>
1023
1024<p>
1025The following is an output example for GPS and GLONASS:
1026<pre>
1027...
1028CUT07 1683 493688.0000000 G05 1C 24584925.242 129195234.317 3639.020 38.812 40 2P 24584927.676 100671636.233 0.0 22.812 -1 2X 24584927.336 100671611.239 0.0 39.500 -1
1029CUT07 1683 493688.0000000 G04 1C 22598643.968 118756563.731 -1589.277 42.625 40 2P 22598649.391 92537559.230 0.0 29.125 -1
1030CUT07 1683 493688.0000000 G02 1C 23290004.062 122389588.008 -445.992 46.375 -1 2P 23290003.567 95368508.986 0.0 29.188 -1
1031
1032CUT07 1683 493689.0000000 R16 -1 1C 19210052.313 102616872.230 364.063 53.375 42 1P 19210053.445 102616393.224 0.0 52.312 42 2P 19210057.785 79813218.557 0.0 50.188 -1
1033CUT07 1683 493689.0000000 R15 0 1C 20665491.149 110430900.266 -2839.875 49.188 -1 1P 20665491.695 110430900.278 0.0 47.625 -1 2P 20665497.559 85890714.522 0.0 48.000 -1
1034CUT07 1683 493689.0000000 R09 -2 1C 22028400.805 117630697.367 3584.840 47.625 -1 1P 22028401.586 117630607.367 0.0 45.688 -1 2P 22028406.746 91490549.182 0.0 41.625 -1
1035CUT07 1683 493689.0000000 R07 5 1C 24291127.360 130032400.255 4146.149 40.125 42 1P 24291128.492 130032400.259 0.0 39.312 42 2P 24291130.602 101136710.408 0.0 35.125 -1
1036CUT07 1683 493689.0000000 R05 1 1C 19740809.867 105526251.571 -921.679 54.125 42 1P 19740809.008 105526273.586 0.0 51.875 42 2P 19740814.051 82075815.588 0.0 50.812 -1
1037CUT07 1683 493689.0000000 R04 6 1C 23394651.125 125277095.951 -3385.191 40.875 42 1P 23394651.906 125277095.943 0.0 39.812 42 2P 23394658.125 97437771.004 0.0 39.000 -1
1038CUT07 1683 493689.0000000 G28 1C 25286905.648 132883677.970 4016.750 36.125 17 2P 25286911.715 103545663.916 0.0 14.812 11
1039CUT07 1683 493689.0000000 G23 1C 23018013.274 120961034.323 -1795.551 46.375 -1 2P 23018011.781 94255379.472 0.0 31.688 -1
1040CUT07 1683 493689.0000000 G20 1C 24055613.563 126413402.503 -3233.574 38.500 -1 2P 24055617.227 98504065.103 0.0 20.125 -1
1041CUT07 1683 493689.0000000 G16 1C 24846810.039 130571661.274 -2140.137 38.000 41 2P 24846811.477 101744166.486 0.0 18.625 -1
1042CUT07 1683 493689.0000000 G13 1C 21388182.664 112395102.592 -678.356 51.812 -1 2P 21388183.516 87580617.458 0.0 39.688 -1
1043CUT07 1683 493689.0000000 G10 1C 20656684.758 108551288.049 1726.191 52.875 -1 2P 20656687.016 84585420.340 0.0 42.625 -1
1044CUT07 1683 493689.0000000 G08 1C 20703057.860 108795261.566 1880.523 52.875 -1 2P 20703060.644 84775535.497 0.0 41.188 -1
1045CUT07 1683 493689.0000000 G07 1C 20200125.289 106152257.500 -603.082 53.312 41 2P 20200126.961 82716251.449 0.0 46.000 -1 2X 20200126.797 82716243.452 0.0 52.625 -1
1046CUT07 1683 493689.0000000 G05 1C 24584232.312 129191595.301 3639.047 38.875 41 2P 24584234.980 100668800.633 0.0 22.875 -1 2X 24584234.348 100668775.639 0.0 39.812 -1
1047CUT07 1683 493689.0000000 G04 1C 22598946.500 118758153.159 -1589.461 42.500 41 2P 22598951.570 92538797.744 0.0 29.125 -1
1048CUT07 1683 493689.0000000 G02 1C 23290088.758 122390034.211 -446.429 46.312 -1 2P 23290088.203 95368856.681 0.0 28.500 -1
1049
1050CUT07 1683 493690.0000000 R16 -1 1C 19209984.633 102616508.497 363.305 53.500 43 1P 19209985.180 102616029.506 0.0 51.812 43 2P 19209989.871 79812935.655 0.0 50.188 -1
1051CUT07 1683 493690.0000000 R15 0 1C 20666023.047 110433740.264 -2840.242 49.188 -1 1P 20666023.945 110433740.275 0.0 47.500 -1 2P 20666029.574 85892923.403 0.0 47.625 -1
1052CUT07 1683 493690.0000000 R09 -2 1C 22027730.398 117627112.720 3584.305 47.688 -1 1P 22027730.828 117627022.726 0.0 46.188 -1 2P 22027735.988 91487761.121 0.0 41.688 -1
1053...
1054</pre>
1055<p>
1056The source code for BNC comes with a perl script called 'test_tcpip_client.pl' that allows you to read BNC's (synchronized or unsynchronized) ASCII observation output from the IP port and print it on standard output.
1057</p>
1058<p>
1059Note that any socket connection of an application to BNC's synchronized or unsynchronized observations ports is recorded in the 'Log' tab on the bottom of the main window together with a connection counter, resulting in log records like 'New client connection on sync/usync port: # 1'.
1060</p>
1061
1062<p>
1063The following figure shows the screenshot of a BNC configuration where a number of streams is pulled from different NTRIP Broadcasters to feed a GNSS engine via IP port output.
1064</p>
1065<p><img src="IMG/screenshot12.png"/></p>
1066<p><u>Figure 10:</u> Synchronized BNC output via IP port to feed a GNSS real-time engine.</p>
1067
1068<p><a name="syncport"><h4>3.8.1 Port - optional</h4></p>
1069<p>
1070BNC can produce synchronized observations in ASCII format on your local host (IP 127.0.0.1) through an IP 'Port'. Synchronized means that BNC collects all observation data for any specific epoch which become available within a certain number of latency seconds (see 'Wait for Full Obs Epoch' option). It then - epoch by epoch - outputs whatever has been received. Specify an IP port number here to activate this function. The default is an empty option field, meaning that no binary synchronized output is generated.</p>
1071</p>
1072
1073<p><a name="syncwait"><h4>3.8.2 Wait for Full Obs Epoch - mandatory if 'Port' is set</h4></p>
1074<p>
1075When feeding a real-time GNSS network engine waiting for synchronized observations epoch by epoch, BNC drops whatever is received later than 'Wait for full obs epoch' seconds. A value of 3 to 5 seconds could be an appropriate choice for that, depending on the latency of the incoming streams and the delay acceptable for your real-time GNSS product. Default value for 'Wait for full obs epoch' is 5 seconds.
1076</p>
1077<p>
1078Note that 'Wait for full obs epoch' does not affect the RINEX Observation file content. Observations received later than 'Wait for full obs epoch' seconds will still be included in the RINEX Observation files.
1079</p>
1080
1081<p><a name="syncsample"><h4>3.8.3 Sampling - mandatory if 'File' or 'Port' is set</h4></p>
1082<p>
1083Select the synchronized observation output sampling interval in seconds. A value of zero '0' tells BNC to send/store all received epochs. This is the default value.
1084</p>
1085
1086<p><a name="syncfile"><h4>3.8.4 File - optional</h4></p>
1087<p>
1088Specify the full path to a 'File' where synchronized observations are saved in plain ASCII format. The default value is an empty option field, meaning that no ASCII output file is created.
1089</p>
1090<p>
1091Beware that the size of this file can rapidly increase depending on the number of incoming streams. This option is primarily meant for testing and evaluation.
1092</p>
1093
1094<p><a name="syncuport"><h4>3.8.5 Port (unsynchronized) - optional</h4></p>
1095<p>
1096BNC can produce unsynchronized observations from all configured streams in ASCII format on your local host (IP 127.0.0.1) through an IP 'Port'. Unsynchronized means that BNC immediately forwards any received observation to the port. Specify an IP port number here to activate this function. The default is an empty option field, meaning that no unsynchronized output is generated.</p>
1097<p>
1098
1099<p><a name="serial"><h4>3.9. Serial Output</h4></p>
1100<p>
1101You may use BNC to feed a serial connected device like a GNSS receiver. For that an incoming stream can be forwarded to a serial port. The following figure shows the screenshot of an example situation where BNC pulls a VRS stream from an NTRIP Broadcaster to feed a serial connected RTK rover.
1102</p>
1103<p><img src="IMG/screenshot11.png"/></p>
1104<p><u>Figure 11:</u> BNC pulling a VRS stream to feed a serial connected RTK rover.</p>
1105
1106<p><a name="sermount"><h4>3.9.1 Mountpoint - optional</h4></p>
1107<p>
1108Enter a 'Mountpoint' to forward its corresponding stream to a serial connected GNSS receiver.
1109</p>
1110<p>
1111When selecting one of the serial communication options listed below, make sure that you pick those configured to the serial connected receiver.
1112</p>
1113
1114<p><a name="serport"><h4>3.9.2 Port Name - mandatory if 'Mountpoint' is set</h4></p>
1115<p>
1116Enter the serial 'Port name' selected on your host for communication with the serial connected receiver. Valid port names are
1117</p>
1118<pre>
1119Windows: COM1, COM2
1120Linux: /dev/ttyS0, /dev/ttyS1
1121FreeBSD: /dev/ttyd0, /dev/ttyd1
1122Digital Unix: /dev/tty01, /dev/tty02
1123HP-UX: /dev/tty1p0, /dev/tty2p0
1124SGI/IRIX: /dev/ttyf1, /dev/ttyf2
1125SunOS/Solaris: /dev/ttya, /dev/ttyb
1126</pre>
1127<p>
1128Note that you must plug a serial cable in the port defined here before you start BNC.
1129</p>
1130
1131<p><a name="serbaud"><h4>3.9.3 Baud Rate - mandatory if 'Mountpoint' is set</h4></p>
1132<p>
1133Select a 'Baud rate' for the serial output link. Note that using a high baud rate is recommended.
1134</p>
1135
1136<p><a name="serflow"><h4>3.9.4 Flow Control - mandatory if 'Mountpoint' is set</h4></p>
1137<p>
1138Select a 'Flow control' for the serial output link. Note that your selection must equal the flow control configured to the serial connected device. Select 'OFF' if you don't know better.
1139</p>
1140
1141<p><a name="serparity"><h4>3.9.5 Parity - mandatory if 'Mountpoint' is set</h4></p>
1142<p>
1143Select the 'Parity' for the serial output link. Note that parity is often set to 'NONE'.
1144</p>
1145
1146<p><a name="serdata"><h4>3.9.6 Data Bits - mandatory if 'Mountpoint' is set</h4></p>
1147<p>
1148Select the number of 'Data bits' for the serial output link. Note that often '8' data bits are used.
1149</p>
1150
1151<p><a name="serstop"><h4>3.9.7 Stop Bits - mandatory if 'Mountpoint' is set</h4></p>
1152<p>
1153Select the number of 'Stop bits' for the serial output link. Note that often '1' stop bit is used.
1154</p>
1155
1156<p><a name="serauto"><h4>3.9.8 NMEA - mandatory for VRS streams</h4></p>
1157<p>
1158Select 'Auto' to automatically forward all NMEA-GGA messages coming from your serial connected GNSS receiver to the NTRIP Broadcaster and/or save them in a file.
1159</p>
1160<p>
1161Forwarding valid NMEA-GGA messages to the NTRIP Broadcaster is required for receiving 'Virtual Reference Station' (VRS) streams. Thus, in case your serial connected receiver is not capable to provide them, the alternative for VRS streams is a 'Manual' simulation of an initial NMEA-GGA message. Its content is based on the approximate (editable) latitude/longitude from the broadcaster's source-table and an approximate VRS height to be specified.
1162</p>
1163<p>
1164In summary: select 'Manual' only when handling a VRS stream and your serial connected GNSS receiver doesn't generate NMEA-GGA messages. Select 'Auto' otherwise.
1165</p>
1166
1167<p><a name="serfile"><h4>3.9.9 File - optional if 'Auto' NMEA is set</h4></p>
1168<p>Specify the full path to a file where NMEA messages coming from your serial connected receiver are saved.
1169</p>
1170<p><a name="serheight"><h4>3.9.10 Height - mandatory if 'Manual' NMEA is set</h4></p>
1171<p>
1172Specify an approximate 'Height' above mean sea level in meter for your VRS to simulate an initial NMEA-GGA message. Latitude and longitude for that (editable) are taken from the broadcaster's source-table.
1173</p>
1174<p>
1175This option concerns only 'Virtual Reference Stations' (VRS). Its setting is ignored in case of streams coming from physical reference stations.
1176</p>
1177
1178<p><a name="advnote"><h4>3.10. Outages</h4></p>
1179
1180<p>
1181At any time an incoming stream might become unavailable or corrupted. In such cases, it is important that the BNC operator and/or the stream providers become aware of the situation so that necessary measures can be taken to restore the stream. Furthermore, continuous attempts to decode a corrupted stream can generate unnecessary workload for BNC. Outages and corruptions are handled by BNC as follows:
1182</p>
1183<p>
1184<u>Stream outages:</u> BNC considers a connection to be broken when there are no incoming data detected for more than 20 seconds. When this occurs, BNC will attempt to reconnect at a decreasing rate. It will first try to reconnect with 1 second delay and again in 2 seconds if the previous attempt failed. If the attempt is still unsuccessful, it will try to reconnect within 4 seconds after the previous attempt and so on. The wait time doubles each time with a maximum wait time of 256 seconds.
1185</p>
1186<p>
1187<u>Stream corruption:</u> Not all bits chunk transfers to BNC's internal decoders return valid observations. Sometimes several chunks might be needed before the next observation can be properly decoded. BNC buffers all the outputs (both valid and invalid) from the decoder for a short time span (size derived from the expected 'Observation rate') and then determines whether a stream is valid or corrupted.
1188</p>
1189<p>
1190Outage and corruption events are reported in the 'Log' tab. They can also be passed on as parameters to a shell script or batch file to generate an advisory note to BNC operator or affected stream providers. This functionality lets users utilize BNC as a real-time performance monitor and alarm system for a network of GNSS reference stations.
1191</p>
1192
1193<p><a name="obsrate"><h4>3.10.1 Observation Rate - mandatory if 'Failure threshold', 'Recovery threshold' and 'Script' is set</h4></p>
1194<p>
1195BNC can collect all returns (success or failure) coming from a decoder within a certain short time span to then decide whether a stream has an outage or its content is corrupted. This procedure needs a rough a priory estimate of the expected observation rate of the incoming streams.</p><p>An empty option field (default) means that you don't want explicit information from BNC about stream outages and incoming streams that cannot be decoded.
1196</p>
1197
1198<p><a name="advfail"><h4>3.10.2 Failure Threshold - optional</h4></p>
1199<p>
1200Event 'Begin_Failure' will be reported if no data is received continuously for longer than the 'Failure threshold' time. Similarly, event 'Begin_Corrupted' will be reported when corrupted data is detected by the decoder continuously for longer than this 'Failure threshold' time. The default value is set to 15 minutes and is recommended so not to inundate user with too many event reports.
1201</p>
1202<p>
1203Note that specifying a value of zero '0' for the 'Failure threshold' will force BNC to report any stream failure immediately. Note also that for using this function you need to specify the 'Observation rate'.
1204</p>
1205
1206<p><a name="advreco"><h4>3.10.3 Recovery Threshold - optional</h4></p>
1207<p>
1208Once a 'Begin_Failure' or 'Begin_Corrupted' event has been reported, BNC will check for when the stream again becomes available or uncorrupted. Event 'End_Failure' or 'End_Corrupted' will be reported as soon as valid observations are again detected continuously throughout the 'Recovery threshold' time span. The default value is set to 5 minutes and is recommended so not to inundate users with too many event reports.
1209</p>
1210<p>
1211Note that specifying a value of zero '0' for the 'Recovery threshold' will force BNC to report any stream recovery immediately. Note also that for using this function you need to specify the 'Observation rate'.
1212</p>
1213
1214<p><a name="advscript"><h4>3.10.4 Script - optional </h4></p>
1215<p>
1216As mentioned previously, BNC can trigger a shell script or a batch file to be executed when one of the events described are reported. This script can be used to email an advisory note to network operator or stream providers. To enable this feature, specify the full path to the script or batch file in the 'Script' field. The affected stream's mountpoint and type of event reported ('Begin_Outage', 'End_Outage', 'Begin_Corrupted' or 'End_Corrupted') will then be passed on to the script as command line parameters (%1 and %2 on Windows systems or $1 and $2 on Unix/Linux/Mac systems) together with date and time information.
1217</p>
1218<p>
1219Leave the 'Script' field empty if you do not wish to use this option. An invalid path will also disable this option.
1220</p>
1221<p>
1222Examples for command line parameter strings passed on to the advisory 'Script' are:
1223<pre>
1224FFMJ0 Begin_Outage 08-02-21 09:25:59
1225FFMJ0 End_Outage 08-02-21 11:36:02 Begin was 08-02-21 09:25:59
1226</pre>
1227</p>
1228<p>
1229Sample script for Unix/Linux/Mac systems:
1230</p>
1231<pre>
1232#!/bin/bash
1233sleep $((60*RANDOM/32767))
1234cat | mail -s &quot;NABU: $1&quot; email@address &lt;&lt;!
1235Advisory Note to BNC User,
1236Please note the following advisory received from BNC.
1237Stream: $*
1238Regards, BNC
1239!
1240</pre>
1241</p>
1242<p>
1243Note the sleep command in this script which causes the system to wait for a random period of up to 60 seconds before sending the email. This should avoid overloading your mail server in case of a simultaneous failure of many streams.
1244</p>
1245
1246<p><a name="misc"><h4>3.11. Miscellaneous</h4></p>
1247<p>
1248This section describes several miscellaneous options which can be applied for a single stream (mountpoint) or for all configured streams.
1249</p>
1250
1251<p>
1252The following figure shows RTCM message numbers and observation types contained in stream 'CUT07' and the message latencies recorded every 2 seconds.
1253</p>
1254<p><img src="IMG/screenshot14.png"/></p>
1255<p><u>Figure 12:</u> RTCM message numbers, latencies and observation types.</p>
1256
1257
1258<p><a name="miscmount"><h4>3.11.1 Mountpoint - optional </h4></p>
1259<p>
1260Specify a mountpoint to apply one or several of the 'Miscellaneous' options to the corresponding stream. Enter 'ALL' if you want to apply these options to all configured streams. An empty option field (default) means that you don't want BNC to apply any of these options.
1261</p>
1262
1263<p><a name="miscperf"><h4>3.11.2 Log Latency - optional </h4></p>
1264<p>
1265 BNC can average latencies per stream over a certain period of GPS time, the 'Log latency' interval. Mean latencies are calculated from the individual latencies of one (first incoming) observation or Broadcast Correction per second. The mean latencies are then saved in BNC's logfile. Note that computing correct latencies requires the clock of the host computer to be properly synchronized. Note further that visualized latencies from the 'Latency' tab on the bottom of the main window represent individual latencies and not the mean latencies for the logfile.
1266</p>
1267<p>
1268<u>Latency:</u> Latency is defined in BNC by the following equation:
1269</p>
1270<pre>
1271 UTC time provided by BNC's host
1272 - GPS time of currently processed epoch
1273 + Leap seconds between UTC and GPS time
1274 --------------
1275 = Latency
1276</pre>
1277<p>
1278<u>Statistics:</u> BNC counts the number of GPS seconds covered by at least one observation. It also estimates an observation rate (independent from the a priory specified 'Observation rate') from all observations received throughout the first full 'Log latency' interval. Based on this rate, BNC estimates the number of data gaps when appearing in subsequent intervals.
1279</p>
1280<p>
1281Latencies of observations or corrections to Broadcast Ephemeris and statistical information can be recorded in the 'Log' tab at the end of each 'Log latency' interval. A typical output from a 1 hour 'Log latency' interval would be:
1282</p>
1283<pre>
128408-03-17 15:59:47 BRUS0: Mean latency 1.47 sec, min 0.66, max 3.02, rms 0.35, 3585 epochs, 15 gaps
1285</pre>
1286<p>
1287Select a 'Log latency' interval to activate this function or select the empty option field if you do not want BNC to log latencies and statistical information.
1288</p>
1289
1290
1291<p><a name="miscscan"><h4>3.11.3 Scan RTCM - optional</h4></p>
1292<p>
1293When configuring a GNSS receiver for RTCM stream generation, the firmware's setup interface may not provide details about RTCM message types observation types. As reliable information concerning stream contents should be available i.e. for NTRIP Broadcaster operators to maintain the broadcaster's source-table, BNC allows to scan RTCM streams for incoming message types and printout some of the contained meta-data. Contained observation types are also printed because such information is required a-priori to the conversion of RTCM Version 3 MSM streams to RINEX Version 3 files. The idea for this option arose from 'InspectRTCM', a comprehensive stream analyzing tool written by D. Stoecker.
1294</p>
1295<p>
1296Tick 'Scan RTCM' to scan RTCM Version 2 or 3 streams and log all contained
1297</p>
1298<ul>
1299<li>Numbers of incoming message types</li>
1300<li>Antenna Reference Point (ARP) coordinates</li>
1301<li>Antenna Phase Center (APC) coordinates</li>
1302<li>Antenna height above marker</li>
1303<li>Antenna descriptor.</li>
1304</ul>
1305In case of RTCM Version 3 MSM streams the output includes
1306<ul>
1307<li>RINEX Version 3 Observation Types</li>
1308</ul>
1309</p>
1310
1311<p>
1312Note that in RTCM Version 2 the message types 18 and 19 carry only the observables of one frequency. Hence it needs two type 18 and 19 messages per epoch to transport the observations from dual frequency receivers.
1313</p>
1314<p>
1315
1316<p>Logged time stamps refer to message reception time and allow understanding repetition rates. Enter 'ALL' if you want to log this information from all configured streams. Beware that the size of the logfile can rapidly increase depending on the number of incoming RTCM streams.
1317</p>
1318<p>This option is primarily meant for testing and evaluation. Use it to figure out what exactly is produced by a specific GNSS receiver's configuration. An empty option field (default) means that you don't want BNC to print the message type numbers and antenna information carried in RTCM streams.
1319</p>
1320
1321<p><a name="pppclient"><h4>3.12. PPP Client</h4></p>
1322<p>
1323BNC can derive coordinates for a rover position following the Precise Point Positioning (PPP) approach. It uses either code or code plus phase data in ionosphere free linear combinations P3 or L3. Besides pulling a stream of observations from a dual frequency receiver, this also
1324<ul>
1325<li>requires pulling in addition a stream carrying satellite orbit and clock corrections to Broadcast Ephemeris in the form of RTCM Version 3 'State Space Representation' (SSR) messages. Note that for BNC these Broadcast Corrections need to be referred to the satellite's Antenna Phase Center (APC). Streams providing such messages are listed on <u>http://igs.bkg.bund.de/ntrip/orbits</u>. Stream 'CLK11' on NTRIP Broadcaster 'products.igs-ip.net:2101' is an example.</li>
1326<li>may require pulling a stream carrying Broadcast Ephemeris available as RTCM Version 3 message types 1019, 1020, and 1045. This is a must only when the stream coming from the receiver does not contain Broadcast Ephemeris or provides them only at very low repetition rate. Streams providing such messages are listed on <u>http://igs.bkg.bund.de/ntrip/ephemeris</u>. Stream 'RTCM3EPH' on caster 'products.igs-ip.net:2101' is an example.</li>
1327</ul>
1328</p>
1329<p>
1330The following figure provides the screenshot of an example PPP session with BNC.
1331</p>
1332
1333<p><img src="IMG/screenshot03.png"/></p>
1334<p><u>Figure 13:</u> Precise Point Positioning with BNC, PPP Panel 1.</p>
1335
1336<p><img src="IMG/screenshot18.png"/></p>
1337<p><u>Figure 14:</u> Precise Point Positioning with BNC, PPP Panel 2.</p>
1338
1339<p>
1340PPP results are shown in the 'Log' tab on the bottom of BNC's main window. Depending on the processing options, the following values are shown about once per second (example):
1341<pre>
134210-09-08 09:14:06 FFMJ1 PPP 09:14:04.0 12 4053457.429 +- 2.323 617730.551 +- 1.630 4869395.266 +- 2.951
1343</pre>
1344</p>
1345<p>
1346The selected mountpoint in that is followed by a PPP time stamp in GPS Time, the number of processed satellites, and XYZ coordinates with their formal errors as derived from the implemented filter in [m]. The implemented algorithm includes outlier and cycle slip detection. The maximum for accepted residuals is hard coded to 10 meters for code observations and 10 centimeters for phase observations.
1347</p>
1348
1349<p>
1350More detailed PPP results are saved in BNC's logfile. Depending on the selected processing options you find
1351<ul>
1352<li>code and phase residuals for GPS and GLONASS and Galileo in [m], </li>
1353<li>receiver clock errors in [m], </li>
1354<li>a-priori and correction values of tropospheric zenith delay in [m],
1355<li>time offset between GPS time and Galileo time in [m],
1356<li>L3 biases, also known as 'floated ambiguities', given per satellite.
1357</ul>
1358These parameters are saved together with their standard deviation. The following is an example extract from a log file when BNC was in 'Single Point Positioning' (SPP) mode:
1359</p>
1360<p>
1361<pre>
136210-12-06 18:10:50 Single Point Positioning of Epoch 18:10:48.0
1363--------------------------------------------------------------
136418:10:48.0 RES G04 L3 0.0165 P3 -0.1250
136518:10:48.0 RES G11 L3 0.0150 P3 0.7904
136618:10:48.0 RES G13 L3 0.0533 P3 0.4854
136718:10:48.0 RES G17 L3 -0.0277 P3 1.2920
136818:10:48.0 RES G20 L3 -0.0860 P3 -0.1186
136918:10:48.0 RES G23 L3 0.0491 P3 -0.1052
137018:10:48.0 RES G31 L3 0.0095 P3 -3.2929
137118:10:48.0 RES G32 L3 0.0183 P3 -3.8800
137218:10:48.0 RES R05 L3 -0.0077
137318:10:48.0 RES R06 L3 0.0223
137418:10:48.0 RES R15 L3 -0.0020
137518:10:48.0 RES R16 L3 0.0156
137618:10:48.0 RES R20 L3 -0.0247
137718:10:48.0 RES R21 L3 0.0014
137818:10:48.0 RES R22 L3 -0.0072
137918:10:48.0 RES E52 L3 -0.0475 P3 -0.1628
138018:10:48.0 RES G04 L3 0.0166 P3 -0.1250
138118:10:48.0 RES G11 L3 0.0154 P3 0.7910
138218:10:48.0 RES G13 L3 0.0535 P3 0.4855
138318:10:48.0 RES G17 L3 -0.0272 P3 1.2925
138418:10:48.0 RES G20 L3 -0.0861 P3 -0.1188
138518:10:48.0 RES G23 L3 0.0489 P3 -0.1055
138618:10:48.0 RES G31 L3 0.0094 P3 -3.2930
138718:10:48.0 RES G32 L3 0.0183 P3 -3.8800
138818:10:48.0 RES R05 L3 -0.0079
138918:10:48.0 RES R06 L3 0.0223
139018:10:48.0 RES R15 L3 -0.0020
139118:10:48.0 RES R16 L3 0.0160
139218:10:48.0 RES R20 L3 -0.0242
139318:10:48.0 RES R21 L3 0.0016
139418:10:48.0 RES R22 L3 -0.0072
139518:10:48.0 RES E52 L3 -0.0474 P3 0.1385
1396
1397 clk = 64394.754 +- 0.045
1398 trp = 2.185 +0.391 +- 0.001
1399 offset = -415.400 +- 0.137
1400 amb G17 = 11.942 +- 0.045
1401 amb G23 = 248.892 +- 0.044
1402 amb G31 = 254.200 +- 0.045
1403 amb G11 = -12.098 +- 0.044
1404 amb G20 = -367.765 +- 0.044
1405 amb G04 = 259.588 +- 0.044
1406 amb E52 = 6.124 +- 0.130
1407 amb G32 = 201.496 +- 0.045
1408 amb G13 = -265.658 +- 0.044
1409 amb R22 = -106.246 +- 0.044
1410 amb R21 = -119.605 +- 0.045
1411 amb R06 = 41.328 +- 0.044
1412 amb R15 = 163.453 +- 0.044
1413 amb R20 = -532.746 +- 0.045
1414 amb R05 = -106.603 +- 0.044
1415 amb R16 = -107.830 +- 0.044
1416</pre>
1417</p>
1418
1419<p>
1420Note that for debugging or Post Processing purposes BNC's 'PPP' functionality option can also be used offline.
1421<ul>
1422<li>
1423<u>Debugging:</u> Apply the 'File Mode' 'Command Line' option for that to read a file containing synchronized observations, orbit and clock correctors, and Broadcast Ephemeris. Such a file must be generated before using BNC's 'Raw output file' option. Example:<br>
1424bnc.exe --conf c:\temp\PPP.bnc --file c:\temp\FFMJ1
1425</li>
1426<li>
1427<u>Post Processing:</u> Apply the 'Post Processing' option as described below.
1428</li>
1429</ul>
1430</p>
1431
1432<p>When using the PPP option, it is important to understand which effects are corrected by BNC.
1433</p>
1434<ul>
1435<li>BNC does correct for Solid Earth Tides and Phase Windup.</li>
1436<li>Satellite antenna phase center offsets are not corrected because applied orbit/clock corrections are referred to the satellite's antenna phase center.</li>
1437<li>Satellite antenna phase center variations are neglected because this is a small effect usually less than 2 centimeters.</li>
1438<li>Observations can be corrected for a Receiver Antenna Offset. Depending on whether or not this correction is applied, the estimated position is either that of the receiver's antenna phase center or that of the receiver's Antenna Reference Point.</li>
1439<li>Receiver antenna phase center variations are not included in the model. The bias caused by this neglect depends on the receiver antenna type. For most antennas it is smaller than a few centimeters.</li>
1440<li>Ocean and atmospheric loading is neglected. Atmospheric loading is pretty small. Ocean loading is usually also a small effect but may reach up to about 10 centimeters for coastal stations.</li>
1441<li>Rotational deformation due to polar motion (Polar Tides) is not corrected because this is a small effect usually less than 2 centimeters.</li>
1442</ul>
1443</p>
1444
1445<p><a name="pppmode"><h4>3.12.1 Mode & Mountpoints - optional</h4></p>
1446<p>
1447Specify the Point Positioning mode you want to apply and the mountpoints for observations and Broadcast Corrections.
1448</p>
1449
1450<p><a name="pppmodus"><h4>3.12.1.1 Mode - optional</h4></p>
1451<p>
1452Choose between plain Single Point Positioning (SPP) and Precise Point Positioning (PPP) in 'Realtime' or 'Post-Processing' mode. Options are 'Realtime-PPP', 'Realtime-SPP', and 'Post-Processing'.
1453</p>
1454
1455<p><a name="pppobsmount"><h4>3.12.1.2 Obs Mountpoint - optional</h4></p>
1456<p>
1457Specify an 'Observations Mountpoint' from the list of selected 'Streams' you are pulling if you want BNC to derive coordinates for the affected rover position through a Point Positioning solution.
1458</p>
1459
1460<p><a name="pppcorrmount"><h4>3.12.1.3 Corr Mountpoint - optional</h4></p>
1461<p>
1462Specify a Broadcast Ephemeris 'Corrections Mountpoint' from the list of selected 'Streams' you are pulling if you want BNC to correct your positioning solution accordingly.
1463</p>
1464
1465<p><a name="pppxyz"><h4>3.12.2 Marker Coordinates - optional</h4></p>
1466<p>
1467Enter the reference coordinate XYZ of the receiver's position in meters if known. This option makes only sense for static observations. Default are empty option fields, meaning that the antenna's XYZ position is unknown.
1468</p>
1469<p>
1470Once a XYZ coordinate is defined, the 'PPP' line in BNC's logfile is extended by North, East and Up displacements to (example):
1471</p>
1472<pre>
147310-08-09 06:01:56 FFMJ1 PPP 06:02:09.0 11 4053457.628 +- 2.639 617729.438 +- 1.180 4869396.447 +- 1.921 NEU -0.908 -0.571 1.629
1474</pre>
1475<p>
1476The parameters following the 'NEU' string provide North, East and Up components of the current coordinate displacement in meters.
1477</p>
1478
1479<p><a name="pppneu"><h4>3.12.3 Antenna Eccentricity - optional</h4></p>
1480<p>
1481You may like to specify North, East and Up components of an antenna eccentricity which is the difference between a nearby marker position and the antenna phase center. If you do so BNC will produce coordinates referring to the marker position and not referring to the antenna phase center.
1482</p>
1483
1484<p><a name="pppoutput"><h4>3.12.4 NMEA & Plot Output - optional</h4></p>
1485<p>
1486BNC allows to output results from Precise Point Positioning in NMEA format. It can also plot a time series of North, East and UP displacements.
1487</p>
1488
1489<p><a name="pppnmeafile"><h4>3.12.4.1 NMEA File - optional</h4></p>
1490<p>
1491The NMEA sentences generated about once per second are pairs of
1492<ul>
1493<li> GPGGA sentences which mainly carry the estimated latitude, longitude, and height values, plus</li>
1494<li> GPRMC sentences which mainly carry date and time information.</li>
1495</ul>
1496</p>
1497<p>
1498Specify the full path to a file where Point Positioning results are saved as NMEA messages. The default value for 'NMEA file' is an empty option field, meaning that BNC will not saved NMEA messages into a file.
1499</p>
1500<p>
1501Note that Tomoji Takasu has written a program called RTKPLOT for visualizing NMEA strings. It is available from <u>http://gpspp.sakura.ne.jp/rtklib/rtklib.htm</u> and compatible with the NMEA file and port output of BNC's 'PPP' client option.
1502</p>
1503
1504<p><a name="pppnmeaport"><h4>3.12.4.2 NMEA Port - optional</h4></p>
1505<p>
1506Specify the IP port number of a local port where Point Positioning results become available as NMEA messages. The default value for 'NMEA Port' is an empty option field, meaning that BNC does not provide NMEA messages vi IP port. Note that the NMEA file output and the NMEA IP port output are the same.
1507</p>
1508<p>
1509NASA's 'World Wind' software (see <u>http://worldwindcentral.com/wiki/NASA_World_Wind_Download</u>) can be used for real-time visualization of positions provided through BNC's NMEA IP output port. You need the 'GPS Tracker' plug-in available from <u>http://worldwindcentral.com/wiki/GPS_Tracker</u> for that. The 'Word Wind' map resolution is not meant for showing centimeter level details.
1510</p>
1511
1512<p><a name="pppplot"><h4>3.12.4.3 PPP Plot - optional</h4></p>
1513<p>
1514PPP time series of North (red), East (green) and Up (blue) displacements will be plotted in the 'PPP Plot' tab when this option is ticked. Values will be either referred to an XYZ reference coordinate (if specified) or referred to the first estimated XYZ coordinate. The sliding PPP time series window will cover the period of the latest 5 minutes.
1515</p>
1516<p>
1517Note that a PPP time series makes only sense for a stationary operated receiver.
1518</p>
1519
1520<p><a name="ppppost"><h4>3.12.5 Post Processing - optional</h4></p>
1521<p>When in 'Post-Processing' mode
1522<ul>
1523<li>specifying a RINEX Observation, a RINEX Navigation and a Broadcast Corrections file leads to a PPP solution.</li>
1524<li>specifying only a RINEX Observation and a RINEX Navigation file and no Broadcast Corrections file leads to a SPP solution.</li>
1525</ul>
1526</p>
1527<p>BNC accepts RINEX Version 2 as well as RINEX Version 3 Observation or Navigation file formats. Files carrying Broadcast Corrections must have the format produced by BNC through the 'Broadcast Corrections' tab.
1528<p>
1529Post Processing PPP results can be saved in a specific output file.
1530</p>
1531
1532<p><a name="ppprecant"><h4>3.12.6 Antennas - optional</h4></p>
1533<p>
1534BNC allows correcting observations for antenna phase center offsets and variations.
1535</p>
1536
1537<p><a name="pppantex"><h4>3.12.6.1 ANTEX File - optional</h4></p>
1538<p>
1539IGS provides a file containing absolute phase center corrections for GNSS satellite and receiver antennas in ANTEX format. Entering the full path to such an ANTEX file is required for correcting observations for antenna phase center offsets and variations. It allows you to specify the name of your receiver's antenna (as contained in the ANTEX file) to apply such corrections.
1540</p>
1541<p>
1542Default is an empty option field, meaning that you don't want to correct observations for antenna phase center offsets and variations.
1543</p>
1544
1545<p><a name="ppprecantenna"><h4>3.12.6.2 Receiver Antenna Name - optional if 'ANTEX File' is set</h4></p>
1546<p>
1547Specify the receiver's antenna name as defined in your ANTEX file. Observations will be corrected for the antenna phase center's offset which may result in a reduction of a few centimeters at max. Corrections for phase center variations are not yet applied by BNC. The specified name must consist of 20 characters. Add trailing blanks if the antenna name has less than 20 characters. Examples:
1548<pre>
1549'JPSREGANT_SD_E ' (no radome)
1550'LEIAT504 NONE' (no radome)
1551'LEIAR25.R3 LEIT' (radome)
1552</pre>
1553</p>
1554<p>
1555Default is an empty option field, meaning that you don't want to correct observations for antenna phase center offsets.
1556</p>
1557
1558<p><a name="pppbasics"><h4>3.12.7 Basics</h4></p>
1559<p>BNC allows using different Point Positioning processing options depending on the capability of the involved receiver and the application in mind. It also allows introducing specific sigmas for code and phase observations as well as for reference coordinates and troposphere estimates. You may also like to carry out your PPP solution in Quick-Start mode or enforce BNC to restart a solution if the length of an outage exceeds a certain threshold.
1560</p>
1561
1562<p><a name="pppphase"><h4>3.12.7.1 Use Phase Obs - optional</h4></p>
1563<p>
1564By default BNC applies a Point Positioning solution using an ionosphere free P3 linear combination of code observations. Tick 'Use phase obs' for an ionosphere free L3 linear combination of phase observations.
1565</p>
1566
1567<p><a name="ppptropo"><h4>3.12.7.2 Estimate Tropo - optional</h4></p>
1568<p>
1569BNC estimates the tropospheric delay according to equation
1570<pre>
1571T(z) = T_apr(z) + dT / cos(z)
1572</pre>
1573where T_apr is the a-priori tropospheric delay derived from Saastamoinen model.
1574</p>
1575<p>
1576By default BNC does not estimate troposphere parameters. Tick 'Estimate tropo' to estimate troposphere parameters together with the coordinates and save T_apr and dT/cos(z) in BNC's log file.
1577</p>
1578
1579<p><a name="pppglo"><h4>3.12.7.3 Use GLONASS - optional</h4></p>
1580<p>
1581By default BNC does not process GLONASS but only GPS observations when in Point Positioning mode. Tick 'Use GLONASS' to use GLONASS observations in addition to GPS (and Galileo if specified) for estimating coordinates in Point Positioning mode.
1582</p>
1583
1584<p><a name="pppgal"><h4>3.12.7.4 Use Galileo - optional</h4></p>
1585<p>
1586By default BNC does not process Galileo but only GPS observations when in Point Positioning mode. Tick 'Use Galileo' to use Galileo observations in addition to GPS (and GLONASS if specified) for estimating coordinates in Point Positioning mode.
1587</p>
1588
1589<p><a name="pppsync"><h4>3.12.7.5 Sync Corr - optional</h4></p>
1590<p>
1591Zero value (or empty field) means that BNC processes each epoch of data immediately after its arrival using satellite clock corrections available at that time. Non-zero value 'Sync Corr' means that the epochs of data are buffered and the processing of each epoch is postponed till the satellite clock corrections not older than 'Sync Corr' are available. Specifying a value of half the update rate of the clock corrections as 'Sync Corr' (i.e. 5 sec) may be appropriate. Note that this causes an additional delay of the PPP solutions in the amount of half of the update rate.
1592</p>
1593<p>
1594Using observations in sync with the corrections can avoid a possible high frequency noise of PPP solutions. Such noise could result from processing observations regardless of how late after a clock correction they were received. Note that applying the 'Sync Corr' option significantly reduces the PPP computation effort for BNC.
1595</p>
1596<p>
1597Default is an empty option field, meaning that you want BNC to process observations immediately after their arrival through applying the latest received clock correction.
1598</p>
1599
1600<p><a name="pppaverage"><h4>3.12.7.6 Averaging - optional if XYZ is set</h4></p>
1601<p>
1602Enter the length of a sliding time window in minutes. BNC will continuously output moving average values and their RMS as computed from those individual values obtained most recently throughout this period. RMS values presented for XYZ coordinates and tropospheric zenith path delays are bias reduced while RMS values for North/East/Up (NEU) displacements are not. Averaged values for XYZ coordinates and their RMS are marked with string &quot;AVE-XYZ&quot; in BNC's log file and 'Log' section while averaged values for NEU displacements and their RMS are marked with string &quot;AVE-NEU&quot; and averaged values for the tropospheric delays and their RMS are marked with string &quot;AVE-TRP&quot;. Example:
1603</p>
1604<pre>
160510-09-08 09:13:05 FFMJ1 AVE-XYZ 09:13:04.0 4053455.948 +- 0.284 617730.422 +- 0.504 4869397.692 +- 0.089
160610-09-08 09:13:05 FFMJ1 AVE-NEU 09:13:04.0 1.043 +- 0.179 0.640 +- 0.456 1.624 +- 0.331
160710-09-08 09:13:05 FFMJ1 AVE-TRP 09:13:04.0 2.336 +- 0.002
1608</pre>
1609<p>
1610Entering any positive value up to 1440 (24h mean value) is allowed. An empty option field (default) means that you don't want BNC to output moving average positions into the log file and the 'Log' section. Note that averaging positions makes only sense for a stationary receiver.
1611</p>
1612
1613<p><a name="pppquick"><h4>3.12.7.7 Quick-Start - optional if XYZ is set</h4></p>
1614<p>
1615Enter the length of a startup period in seconds for which you want to fix the PPP solution to a known XYZ coordinate. Constraining coordinates is done in BNC through setting the 'XYZ White Noise' temporarily to zero.
1616</p>
1617<p>
1618This so-called Quick-Start option allows the PPP solutions to rapidly converge after startup. It requires that the antenna remains unmoved on the know position throughout the defined period. A value of 60 is likely to be an appropriate choice for 'Quick-Start'. Default is an empty option field, meaning that you don't want BNC to start in 'Quick-Start' mode.
1619<p>
1620You may need to create your own reference coordinate through running BNC for an hour in normal mode before applying the 'Quick-Start' option. Don't forget to introduce a realistic sigma 'XYZ Ini' according to the coordinate's precision.
1621</p>
1622
1623<p><img src="IMG/screenshot17.png"/></p>
1624<p><u>Figure 15:</u> BNC in 'Quick-Start' mode (PPP, Panel 1)</p>
1625
1626<p><img src="IMG/screenshot22.png"/></p>
1627<p><u>Figure 16:</u> BNC in 'Quick-Start' mode (PPP, Panel 2)</p>
1628
1629<p><a name="pppgap"><h4>3.12.7.8 Maximal Solution Gap - optional if Quick-Start is set</h4></p>
1630<p>
1631Specify a 'Maximum Solution Gap' in seconds. Should the time span between two consecutive solutions exceed this limit, the algorithm returns into the 'Quick-Start' mode and fixes the introduced reference coordinate for the specified 'Quick-Start' period. A value of '60' seconds could be an appropriate choice.
1632</p>
1633<p>
1634This option makes only sense for a stationary operated receiver where solution convergence can be enforced because a good approximation for the rover position is known. Default is an empty option field, meaning that you don't want BNC to return into the 'Quick-Start' mode after failures caused i.e. by longer lasting outages.
1635</p>
1636
1637<p><a name="pppsigmas"><h4>3.12.8 Sigmas</h4></p>
1638<p>
1639You may like to introduce specific sigmas for code and phase observations and for the estimation of troposphere parameters.
1640</p>
1641
1642<p><a name="pppsigc"><h4>3.12.8.1 Code - mandatory if 'Use Phase Obs' is set</h4></p>
1643<p>
1644When 'Use phase obs' is set in BNC, the PPP solution will be carried out using both, code and phase observations. A sigma of 10.0 m for code observations and a sigma of 0.02 m for phase observations (defaults) are used to combine both types of observations. As the convergence characteristic of a PPP solution can be influenced by the ratio of the sigmas for code and phase, you may like to introduce you own sigmas for code and phase observations which differ from the default values.
1645<ul>
1646<li>Introducing a smaller sigma (higher accuracy) for code observations or a larger sigma for phase observations leads to better results shortly after program start. However, it may take more time till you finally get the best possible solution.</li>
1647<li>Introducing a larger sigma (lower accuracy) for code observations or a smaller sigma for phase observations may lead to less accurate results shortly after program start and thus a prolonged period of convergence but could provide better positions in the long run.</li>
1648</ul>
1649</p>
1650<p>
1651Specify a sigma for code observations. Default is 10.0 m.
1652</p>
1653
1654<p><a name="pppsigp"><h4>3.12.8.2 Phase - mandatory if 'Use Phase Obs' is set</h4></p>
1655<p>
1656Specify a sigma for phase observations. Default is 0.02 m.
1657</p>
1658
1659<p><a name="pppsigxyzi"><h4>3.12.8.3 XYZ Init - mandatory</h4></p>
1660<p>
1661Enter a sigma in meters for the initial XYZ coordinate. A value of 100.0 (default) may be an appropriate choice. However, this value may be significantly smaller (i.e. 0.01) when starting for example from a station with known XZY position in Quick-Start mode.
1662</p>
1663
1664<p><a name="pppsigxyzn"><h4>3.12.8.4 XYZ White Noise - mandatory</h4></p>
1665<p>
1666Enter a sigma in meters for the 'White Noise' of estimated XYZ coordinate components. A value of 100.0 (default) may be appropriate when considering possible sudden movements of a rover.
1667</p>
1668
1669<p><a name="pppsigtrpi"><h4>3.12.8.5 Tropo Init - mandatory if 'Estimate tropo' is set</h4></p>
1670<p>
1671Enter a sigma in meters for the a-priory model based tropospheric delay estimation. A value of 0.1 (default) may be an appropriate choice.
1672</p>
1673
1674<p><a name="pppsigtrpn"><h4>3.12.8.6 Tropo White Noise - mandatory if 'Estimate tropo' is set</h4></p>
1675<p>
1676Enter a sigma in meters per second to describe the expected variation of the tropospheric effect. Supposing 1Hz observation data, a value of 3e-6 (default) would mean that the tropospheric effect may vary for 3600 * 3e-6 = 0.01 meters per hour.
1677</p>
1678
1679<p><a name="combi"><h4>3.13. Combine Corrections</h4></p>
1680<p>
1681BNC allows processing several orbit and clock correction streams in real-time to produce, encode, upload and save a combination of Broadcast Corrections from various providers. It is so far only the satellite clock corrections which are combined while orbit corrections in the combination product as well as the product update rates are just taken over from one of the incoming Broadcast Correction streams. Combining only clock corrections using a fixed orbit reference has the possibility to introduce some analysis inconsistencies. We may therefore eventually consider improvements on this approach. The clock combination can be based either on a plain 'Single-Epoch' or on a 'Kalman' Filter approach.
1682</p>
1683<p>
1684In the Kalman Filter approach satellite clocks estimated by individual Analyses Centers (ACs) are used as pseudo observations within the adjustment process. Each observation is modeled as a linear function (actually a simple sum) of three estimated parameters: AC specific offset, satellite specific offset common to all ACs, and the actual satellite clock correction which represents the result of the combination. These three parameter types differ in their statistical properties. The satellite clock offsets are assumed to be static parameters while AC specific and satellite specific offsets are stochastic parameters with appropriate white noise.
1685 The solution is regularized by a set of minimal constraints.
1686</p>
1687<p>
1688Removing the AC-dependent biases as well as possible is a major issue with clock combinations. Since they vary in time, it can be tricky to do this. Otherwise, there will be artificial jumps in the combined clock stream if one or more AC contributions drop out for certain epochs. Here the Kalman Filter approach is expected to do better than the Single-Epoch approach.
1689</p>
1690<p>
1691In view of IGS real-time products, the 'Combine Corrections' functionality has been integrated in BNC because
1692<ul>
1693<li>the software with its Graphic User Interface and wide range of supported Operating Systems represents a perfect platform to process many Broadcast Correction streams in parallel;</li>
1694<li>outages of single AC product streams can be mitigated through merging several incoming streams into a combined product;</li>
1695<li>generating a combination product from several AC products allows detecting and rejecting outliers;</li>
1696<li>a Combination Center (CC) can operate BNC to globally disseminate a combination product via NTRIP broadcast;</li>
1697<li>an individual AC could prefer to disseminate a stream combined from primary and backup IT resources to reduce outages;</li>
1698<li>it enables a BNC PPP user to follow his own preference in combining streams from individual ACs for Precise Point Positioning;</li>
1699<li>it allows an instantaneous quality control of the combination process not only in the time domain but also in the space domain; this can be done through direct application of the combined stream in a PPP solution even without prior upload to an NTRIP Broadcaster;</li>
1700<li>it provides the means to output SP3 and Clock RINEX files containing precise orbit and clock information for further processing using other tools than BNC.</li>
1701</ul>
1702</p>
1703<p>
1704Note that the combination process requires real-time access to Broadcast Ephemeris. So, in addition to the orbit and clock correction streams BNC must pull a stream carrying Broadcast Ephemeris in the form of RTCM Version 3 messages. Stream 'RTCM3EPH' on caster <u>products.igs-ip.net</u> is an example for that.
1705</p>
1706<p>
1707Note further that you need to tick the 'Use GLONASS' option which is part ot the 'PPP (2)' panel in case you want to produce an GPS plus GLONASS combination.
1708</p>
1709<p>
1710A combination is carried out following a specified sampling interval. If incoming streams have different rates, only epochs that correspond to the sampling interval are used.
1711</p>
1712<p>
1713With respect to IGS, it is important to understand that a major effect in the combination of GNSS orbit and clock correction streams is the selection of ACs to include. It is likely that a combination product could be improved in accuracy by using only the best two or three ACs. However, with only a few ACs to depend on, the reliability of the combination product could suffer and the risk of total failures increases. So there is an important tradeoff here that must be considered when selecting streams for a combination. The major strength of a combination product is its reliability and stable median performance which can be much better than that of any single AC product.
1714</p>
1715<p>
1716This comment applies in situations where we have a limited number of solutions to combine and their quality varies significantly. The situation may be different when the total number of ACs is larger and the range of AC variation is smaller. In that case, a standard full combination is probably the best.
1717</p>
1718<p>
1719The following recursive algorithm is used to detect orbit outliers in the Kalman Filter combination when Broadcast Corrections are provided by several ACs:
1720<br>
1721Step 1: We don't produce a combination for a certain satellite if only one AC provides corrections for it.
1722<br>
1723Step 2: A mean satellite position is calculated as the average of positions from all ACs.
1724<br>
1725Step 3: For each AC and satellite the 3D distance between individual and mean satellite position is calculated.
1726<br>
1727Step 4: We find the greatest difference between AC specific and mean satellite positions.
1728<br>
1729Step 5: If that is less than a threshold, the conclusion is that we don't have an outlier and can proceed to the next epoch.
1730<br>
1731Step 6: If that is greater than a threshold, then corrections of the affiliated AC are ignored for the affected epoch and the outlier detection restarts with step 1.
1732</p>
1733<p>
1734Note that BNC can produce an internal PPP solution from combined Broadcast Corrections. For that you have to specify the keyword 'INTERNAL' as 'Corrections Mountpoint' in the PPP (1) panel.
1735</p>
1736<p>
1737The part of BNC which enables the combination of Broadcast Corrections is not intended for publication under GNU General Public License (GPL). However, pre-compiled BNC binaries which support the 'Combine Corrections' option are made available.
1738</p>
1739
1740<p><a name="combimounttab"><h4>3.13.1 Combine Corrections Table - optional</h4></p>
1741<p>
1742Hit the 'Add Row' button, double click on the 'Mountpoint' field, enter a Broadcast Corrections mountpoint from the 'Streams' section and hit Enter. Then double click on the 'AC Name' field to enter your choice of an abbreviation for the Analysis Center (AC) providing the stream. Finally, double click on the 'Weight' field to enter a weight to be applied to this stream in the combination. The stream processing can already be started with only one corrections stream configured for combination.
1743</p>
1744<p>
1745Note that an appropriate 'Wait for full corr epoch' value needs to be specified for the combination under the 'Broadcast Corrections' tab. To give an example: a value of 15 sec would make sense if the update rate of incoming clock corrections is 10 sec.
1746</p>
1747<p>
1748The sequence of entries in the 'Combine Corrections' table is not of importance. Note that the orbit information in the final combination stream is just copied from one of the incoming streams. The stream used for providing the orbits may vary over time: if the orbit providing stream has an outage then BNC switches to the next remaining stream for getting hold of the orbit information.</p>
1749<p>
1750Default is an empty 'Combine Corrections' table meaning that you don't want BNC to combine orbit and clock correction streams.
1751</p>
1752<p>
1753It is possible to specify only one Broadcast Ephemeris corrections stream in the 'Combine Corrections' table. Instead of combining corrections from several sources BNC will then merge the single corrections stream with Broadcast Ephemeris to save results in SP3 and/or Clock RINEX format when specified accordingly under the 'Upload Corrections' tab.
1754</p>
1755
1756<p><a name="combiadd"><h4>3.13.1.1 Add Row, Delete - optional</h4></p>
1757<p>
1758Hit 'Add Row' button to add another row to the 'Combine Corrections' table or hit the 'Delete' button to delete the highlighted row(s).
1759</p>
1760
1761<p>
1762The following screenshots describe an example setup of BNC when combining Broadcast Correction streams and uploading them to an NTRIP Broadcaster. Note that it requires specifying options under tabs 'Combine Corrections' and 'Upload Corrections'. The example uses the combination product to simultaneously carry out an 'INTERNAL' PPP solution in 'Quick-Start' mode which allows monitoring the quality of the combination product in the space domain.
1763</p>
1764
1765<br>
1766<p><img src="IMG/screenshot20.png"/></p>
1767<p><u>Figure 17:</u> BNC combining Broadcast Correction streams.</p>
1768<p><br></p>
1769<p><img src="IMG/screenshot21.png"/></p>
1770<p><u>Figure 18:</u> BNC uploading the combined Broadcast Corrections stream.</p>
1771<p></p>
1772<p><img src="IMG/screenshot23.png"/></p>
1773<p><u>Figure 19:</u> 'INTERNAL' PPP with BNC using combined Broadcast Corrections stream.</p>
1774
1775<p><a name="combimethod"><h4>3.13.1.2 Method - mandatory if 'Combine Corrections' table is populated</h4></p>
1776<p>
1777Select a clock combination method. Available options are Kalman 'Filter' and 'Single-Epoch. It is suggested to use the Kalman Filter approach in case the combined stream of Broadcast Corrections is intended for Precise Point Positioning.
1778</p>
1779
1780<p><a name="combimax"><h4>3.13.1.3 Maximal Residuum - mandatory if 'Combine Corrections' table is populated</h4></p>
1781
1782<p>BNC combines all incoming clocks according to specified weights. Individual clock estimates that differ by more than 'Maximal Residuum' meters from the average of all clocks will be ignored.<p>
1783</p>It is suggested to specify a value of about 0.2 m for the Kalman filter combination approach and a value of about 3.0 meters for the Single-Epoch combination approach.</p>
1784<p>Default is a 'Maximal Residuum' of 999.0 meters</p>
1785
1786<p><a name="combismpl"><h4>3.13.1.4 Sampling - mandatory if 'Combine Corrections' table is populated</h4></p>
1787<p>Specify a combination sampling interval. Clock and orbit corrections will be produced following that interval. A value of 10 sec may be an appropriate choice.</p>
1788
1789
1790<p><a name="upclk"><h4>3.14. Upload Corrections</h4></p>
1791<p>
1792BNC can upload streams carrying orbit and clock corrections to Broadcast Ephemeris in radial, along-track and cross-track components if they are<ol type=a>
1793<li>
1794either generated by BNC as a combination of several individual Broadcast Correction streams coming from an number of real-time Analysis Centers (ACs), see section 'Combine Corrections',</li>
1795<li>
1796or generated by BNC while the program receives an ASCII stream of precise satellite orbits and clocks via IP port from a connected real-time GNSS engine. Such a stream would be expected in a plain ASCII format and the associated 'decoder' string would have to be 'RTNET', see format description below. </li>
1797</ol>
1798The procedure taken by BNC to generate the clock and orbit corrections to Broadcast Ephemeris and upload them to an NTRIP Broadcaster is as follow:
1799<ul>
1800<li>Continuously receive up-to-date Broadcast Ephemeris carrying approximate orbits and clocks for all satellites. Read new Broadcast Ephemeris immediately whenever they become available. This information may come via a stream of RTCM messages generated from another BNC instance.</li>
1801</ul>
1802Then, epoch by epoch:
1803<ul>
1804<li>Continuously receive the best available clock and orbit estimates for all satellites in XYZ Earth-Centered-Earth-Fixed IGS08 reference system. Receive them every epoch in plain ASCII format as provided by a real-time GNSS engine such as RTNet or generate them following a combination approach. </li>
1805<li>Calculate XYZ coordinates from Broadcast Ephemeris orbits. </li>
1806<li>Calculate differences dX,dY,dZ between Broadcast Ephemeris and IGS08 orbits. </li>
1807<li>Transform these differences into radial, along-track and cross-track corrections to Broadcast Ephemeris orbits. </li>
1808<li>Calculate corrections to Broadcast Ephemeris clocks as differences between Broadcast Ephemeris clocks and IGS08 clocks. </li>
1809<li>Encode Broadcast Ephemeris clock and orbit corrections in RTCM Version 3 format. </li>
1810<li>Upload Broadcast Corrections stream to NTRIP Broadcaster. </li>
1811</ul>
1812<p>
1813The orbit and clock corrections to Broadcast Ephemeris are usually referred to the latest set of broadcast messages, which are generally also received in real-time by a GNSS rover. However, the use of the latest broadcast message is delayed for a period of 60 seconds, measured from the time of complete reception of ephemeris and clock parameters, in order to accommodate rover applications to obtain the same set of broadcast orbital and clock parameters. This procedure is recommended in the RTCM SSR standard.
1814</p>
1815</p>
1816Because the encoding process may put a significant load on the communication link between BNC and the real-time GNSS engine, it is recommended to run both programs on the same host. However, doing so is not compulsory.
1817</p>
1818<p>
1819The usual handling of BNC when uploading a stream with Broadcast Corrections is that you first specify Broadcast Ephemeris and Broadcast Correction streams. You then specify an NTRIP Broadcaster for stream upload before you start the program.
1820</p>
1821<p>
1822BNC requires GNSS clocks and orbits in the IGS Earth-Centered-Earth-Fixed (ECEF) reference system and in a specific ASCII format. The clocks and orbits must be referred to satellite Center of Mass (CoM) and must not contain the conventional periodic relativistic effect. They may be provided by a real-time GNSS engine such as RTNet. The sampling interval for data transmission should not exceed 15 sec. Note that otherwise tools involved in IP streaming such as NTRIP Broadcasters or NTRIP Clients may respond with a timeout.
1823</p>
1824
1825<p>
1826Below you find an example of precise clocks and orbits coming in ASCII format (which is named 'RTNET' in this document) from a real-time GNSS engine. Each epoch starts with an asterisk character followed by the time as year, month, day of month, hour, minute and second. Subsequent records provide the following set of parameters for each satellite:
1827</p>
1828
1829<p>
1830<ul>
1831<li>GNSS Indicator and Satellite Vehicle Pseudo Random Number</li>
1832<li>XYZ coordinates in Earth-Centered-Earth-Fixed system [km] at epoch T</li>
1833<li>Satellite clock error [microsecond]</li>
1834<li>Conventional periodic relativistic effect [microsecond]</li>
1835<li>DX,DY,DZ [m] in Earth-Centered-Earth-Fixed system for translation CoM-&gt;APC</li>
1836<li>Differential Code Bias P1C1 [m]</li>
1837<li>Differential Code Bias P1P2 [m]</li>
1838<li>Time increment dT [second]</li>
1839<li>XYZ coordinates in Earth-Centered-Earth-Fixed system [km] at epoch T+dT</li>
1840</ul>
1841</p>
1842Example for 'RTNET' stream format:
1843</p>
1844<p>
1845<pre>
1846...
1847PR22 24695.278546 4939.628474 -3498.468864 41.074663 0.000301 -2.458 0.059 0.259 0.000 0.369 60.0 24724.926665 4937.395818 -3285.525249
1848PR23 16644.528151 -4673.966731 -18755.727311 -381.408485 -0.000069 -1.484 0.958 1.597 0.000 -1.041 60.0 16794.540110 -4640.370673 -18629.931406
1849PR24 -835.564016 -11361.061950 -22837.329550 -67.978344 -0.000027 0.088 1.593 1.979 0.000 0.628 60.0 -654.746874 -11311.272410 -22867.926411
1850EOE
1851* 2012 4 13 18 5 20.00000000
1852PG01 -17662.477581 -4690.968816 19273.403670 247.562657 -0.001403 1.173 -0.094 -1.222 -0.081 -3.222 60.0 -17723.637492 -4824.411250 19184.308406
1853PG02 13499.913230 23158.540481 -1230.022763 386.539840 -0.009664 -0.392 -0.672 0.036 -0.007 1.778 60.0 13488.200264 23175.574718 -1044.681214
1854PG03 -16691.614702 -11720.144912 -17619.363518 35.472262 -0.007906 1.785 0.965 1.939 -0.171 -0.769 60.0 -16563.914187 -11742.834794 -17725.636699
1855...
1856PG32 -16198.232316 -3364.836652 20899.169198 -432.258718 -0.025811 1.728 0.075 -2.191 -0.370 -1.040 60.0 -16107.271625 -3493.294042 20951.654447
1857PR01 18574.288277 -17410.663026 -1754.600023 -178.990271 -0.000082 -1.469 2.095 0.024 0.000 0.188 60.0 18556.963974 -17406.362476 -1967.750384
1858PR02 8030.345235 -18665.480490 15430.035833 -298.816088 -0.000568 -0.516 2.171 -1.184 0.000 0.221 60.0 8114.572636 -18759.449343 15271.294411
1859PR03 -6108.423573 -9263.873363 23002.679850 -129.074986 0.000627 0.523 1.396 -2.019 0.000 1.568 60.0 -5976.535477 -9398.317054 22982.703956
1860...
1861PR24 -820.514575 -11356.881507 -22839.954618 -67.978328 -0.000026 0.087 1.593 1.979 0.000 0.628 60.0 -639.657024 -11307.160404 -22870.387083
1862EOE
1863* 2012 4 13 18 5 25.00000000
1864PG01 -17667.568396 -4702.119849 19266.035352 247.562677 -0.001403 1.173 -0.094 -1.222 -0.081 -3.222 60.0 -17728.740899 -4835.494883 19176.817383
1865PG02 13498.959815 23160.004885 -1214.580934 386.539856 -0.009647 -0.392 -0.672 0.035 -0.007 1.778 60.0 13487.197253 23176.941260 -1029.232392
1866PG03 -16680.999851 -11722.017340 -17628.269050 35.472285 -0.007882 1.783 0.966 1.940 -0.171 -0.769 60.0 -16553.240904 -11744.747432 -17734.434260
1867...
1868</pre>
1869</p>
1870<p>
1871Note that each end of an epoch in the incoming stream is indicated by an ASCII string 'EOE' (for End Of Epoch).
1872</p>
1873<p>
1874When using clocks from Broadcast Ephemeris (with or without applied corrections) or clocks from SP3 files, it may be important to understand that they are not corrected for the conventional periodic relativistic effect. Chapter 10 of the IERS Conventions 2003 mentions that the conventional periodic relativistic correction to the satellite clock (to be added to the broadcast clock) is computed as dt = -2 (R * V) / c^2 where R *V is the scalar product of the satellite position and velocity and c is the speed of light. This can also be found in the GPS Interface Specification, IS-GPS-200, Revision D, 7 March 2006.
1875</p>
1876
1877<p><a name="upadd"><h4>3.14.1 Add, Delete Row - optional</h4></p>
1878<p>Hit 'Add Row' button to add another row to the stream 'Upload Table' or hit the 'Delete' button to delete the highlighted row(s).
1879</p>
1880<p>
1881Having an empty 'Upload Table' is default and means that you don't want BNC to upload orbit and clock correction streams to any NTRIP Broadcaster.
1882</p>
1883
1884<p><a name="uphost"><h4>3.14.2 Host, Port, Mountpoint, Password - mandatory if 'Upload Table' entries specified</h4></p>
1885
1886<p>Specify the domain name or IP number of an NTRIP Broadcaster for uploading the stream. Furthermore, specify the caster's listening IP port, an upload mountpoint and an upload password. Note that NTRIP Broadcasters are often configured to provide access on more than one port, usually port 80 and 2101. If you experience communication problems on port 80, you should try to use the alternative port(s).
1887</p>
1888<p>
1889BNC uploads a stream to the NNTRIP Broadcaster by referring to a dedicated mountpoint that has been set by its operator. Specify here the mountpoint based on the details you received for your stream from the operator. It is often a four character ID (capital letters) plus an integer number.</p>
1890<p>The stream upload may be protected through an upload 'Password'. Enter the password you received from the NTRIP Broadcaster operator along with the mountpoint(s).</p>
1891<p>
1892If 'Host', 'Port', 'Mountpoint' and 'Password' are set, the stream will be encoded in RTCM's 'State Space Representation' (SSR) messages and uploaded to the specified broadcaster following the NTRIP Version 1 transport protocol.
1893</p>
1894
1895<p><a name="upsystem"><h4>3.14.3 System - mandatory if 'Host' is set</h4></p>
1896<p>
1897BNC allows to configure several Broadcast Correction streams for upload so that they refer to different reference systems and different NTRIP Broadcasters. You may use this functionality for parallel support of a backup NTRIP Broadcaster or for simultaneous support of several reference systems. Available options for referring clock and orbit corrections to specific target reference systems are
1898<p>
1899<ul>
1900<li>IGS08 which stands for the GNSS-based IGS realization of the International Terrestrial Reference Frame 2008 (ITRF2008), and</li>
1901<li>ETRF2000 which stands for the European Terrestrial Reference Frame 2000 adopted by EUREF, and</li>
1902<li>NAD83 which stands for the North American Datum 1983 as adopted for the U.S.A., and</li>
1903<li>GDA94 which stands for the Geodetic Datum Australia 1994 as adopted for Australia, and</li>
1904<li>SIRGAS2000 which stands for the Geodetic Datum adopted for Brazil, and</li>
1905<li>SIRGAS95 which stands for the Geodetic Datum adopted i.e. for Venezuela, and</li>
1906<li>'Custom' which allows a transformation of Broadcast Corrections from the IGS08 system to any other system through specifying up to 14 Helmert Transformation Parameters.</li>
1907</ul>
1908</p>
1909
1910<p>
1911BNC only transforms the original IGS08 <u>orbits</u> in the Broadcast Corrections stream to a target reference system while leaving the clocks unchanged. From a theoretical point of view this leads to inconsistencies between orbits and clocks and is therefore not allowed. However, it has been shown by Huisman et al. 2012 that as long as involved scale parameters are small enough, this way of transforming corrections stream contents only leads to height biases less than about one centimeter. With regards to the systems listed above, the approach has therefore been implemented in BNC for practical reasons.
1912</p>
1913<p>
1914The transformation to <u>GDA94 is an exception</u> in this because it involves a ten times higher scale parameter compared to the other transformations. Note that hence the resulting height biases for a BNC-transformed GDA94 corrections stream can increase up to about 10 centimeters.
1915</p>
1916
1917<p>
1918<u>IGS08:</u> As the clocks and orbits coming from real-time GNSS engine are expected to be in the IGS08 system, no transformation is carried out if this option is selected.
1919</p>
1920
1921<p>
1922<u>ETRF2000:</u> The formulas for the transformation 'ITRF2005-&gt;ETRF2000' are taken from 'Claude Boucher and Zuheir Altamimi 2008: Specifications for reference frame fixing in the analysis of EUREF GPS campaign', see <u>http://etrs89.ensg.ign.fr/memo-V8.pdf</u>. The following 14 Helmert Transformation Parameters were introduced:
1923</p>
1924<p>
1925<pre>
1926Translation in X at epoch To: 0.0521 m
1927Translation in Y at epoch To: 0.0493 m
1928Translation in Z at epoch To: -0.0585 m
1929Translation rate in X: 0.0001 m/y
1930Translation rate in Y: 0.0001 m/y
1931Translation rate in Z: -0.0018 m/y
1932Rotation in X at epoch To: 0.891 mas
1933Rotation in Y at epoch To: 5.390 mas
1934Rotation in Z at epoch To: -8.712 mas
1935Rotation rate in X: 0.081 mas/y
1936Rotation rate in Y: 0.490 mas/y
1937Rotation rate in Z: -0.792 mas/y
1938Scale at epoch To : 0.00000000134
1939Scale rate: 0.00000000008 /y
1940To: 2000.0
1941</pre>
1942</p>
1943
1944<p>
1945<u>NAD83:</u> Formulas for the transformation 'ITRF2005-&gt;NAD83' are taken from 'Chris Pearson, Robert McCaffrey, Julie L. Elliott, Richard Snay 2010: HTDP 3.0: Software for Coping with the Coordinate Changes Associated with Crustal Motion, Journal of Surveying Engineering'.
1946</p>
1947<p>
1948<pre>
1949Translation in X at epoch To: 0.9963 m
1950Translation in Y at epoch To: -1.9024 m
1951Translation in Z at epoch To: -0.5219 m
1952Translation rate in X: 0.0005 m/y
1953Translation rate in Y: -0.0006 m/y
1954Translation rate in Z: -0.0013 m/y
1955Rotation in X at epoch To: 25.915 mas
1956Rotation in Y at epoch To: 9.426 mas
1957Rotation in Z at epoch To: 11.599 mas
1958Rotation rate in X: 0.067 mas/y
1959Rotation rate in Y: -0.757 mas/y
1960Rotation rate in Z: -0.051 mas/y
1961Scale at epoch To : 0.00000000078
1962Scale rate: -0.00000000010 /y
1963To: 1997.0
1964</pre>
1965</p>
1966
1967<p>
1968<u>GDA94:</u> The formulas for the transformation 'ITRF2000-&gt;GDA94' are taken from 'John Dawson, Alex Woods 2010: ITRF to GDA94 coordinate transformations', Journal of Applied Geodesy, 4 (2010), 189¿199, de Gruyter 2010. DOI 10.1515/JAG.2010.019'.
1969</p>
1970<p>
1971<pre>
1972Translation in X at epoch To: -0.07973 m
1973Translation in Y at epoch To: -0.00686 m
1974Translation in Z at epoch To: 0.03803 m
1975Translation rate in X: 0.00225 m/y
1976Translation rate in Y: -0.00062 m/y
1977Translation rate in Z: -0.00056 m/y
1978Rotation in X at epoch To: 0.0351 mas
1979Rotation in Y at epoch To: -2.1211 mas
1980Rotation in Z at epoch To: -2.1411 mas
1981Rotation rate in X: -1.4707 mas/y
1982Rotation rate in Y: -1.1443 mas/y
1983Rotation rate in Z: -1.1701 mas/y
1984Scale at epoch To : 0.000000006636
1985Scale rate: 0.000000000294 /y
1986To: 1994.0
1987</pre>
1988</p>
1989
1990<p>
1991<u>SIRGAS2000:</u> The formulas for the transformation 'ITRF2005-&gt;SIRGAS2000' were provided via personal communication from CGED-Coordenacao de Geodesia, IBGE/DGC - Diretoria de Geociencias, Brazil.</u>.
1992</p>
1993<p>
1994<pre>
1995Translation in X at epoch To: -0.0051 m
1996Translation in Y at epoch To: -0.0065 m
1997Translation in Z at epoch To: -0.0099 m
1998Translation rate in X: 0.0000 m/y
1999Translation rate in Y: 0.0000 m/y
2000Translation rate in Z: 0.0000 m/y
2001Rotation in X at epoch To: 0.150 mas
2002Rotation in Y at epoch To: 0.020 mas
2003Rotation in Z at epoch To: 0.021 mas
2004Rotation rate in X: 0.000 mas/y
2005Rotation rate in Y: 0.000 mas/y
2006Rotation rate in Z: 0.000 mas/y
2007Scale at epoch To : 0.000000000000
2008Scale rate: -0.000000000000 /y
2009To: 2000.0
2010</pre>
2011</p>
2012
2013<p>
2014<u>SIRGAS95:</u> The formulas for the transformation 'ITRF2005-&gt;SIRGAS95' were provided via personal communication from Gustavo Acuha, Laboratorio de Geodesia Fisica y Satelital at Zulia University (LGFS-LUZ), parameters based on values from Table 4.1 of "Terrestrial Reference Frames (April 10, 2009), Chapter 4" in http://tai.bipm.org/iers/convupdt/convupdt_c4.html.</u>.
2015</p>
2016<p>
2017<pre>
2018Translation in X at epoch To: 0.0077 m
2019Translation in Y at epoch To: 0.0058 m
2020Translation in Z at epoch To: -0.0138 m
2021Translation rate in X: 0.0000 m/y
2022Translation rate in Y: 0.0000 m/y
2023Translation rate in Z: 0.0000 m/y
2024Rotation in X at epoch To: 0.000 mas
2025Rotation in Y at epoch To: 0.000 mas
2026Rotation in Z at epoch To: -0.003 mas
2027Rotation rate in X: 0.000 mas/y
2028Rotation rate in Y: 0.000 mas/y
2029Rotation rate in Z: 0.000 mas/y
2030Scale at epoch To : 0.00000000157
2031Scale rate: -0.000000000000 /y
2032To: 1995.4
2033</pre>
2034</p>
2035
2036<p>
2037<u>Custom:</u> The default numbers shown as examples are those for a transformation from ITRF2005 to ETRF2000'.
2038</p>
2039
2040<p><a name="upcom"><h4>3.14.4 Center of Mass - optional</h4></p>
2041<p>
2042BNC allows to either refer Broadcast Corrections to the satellite's Center of Mass (CoM) or to the satellite's Antenna Phase Center (APC). By default corrections refer to APC. Tick 'Center of Mass' to refer uploaded corrections to CoM.
2043</p>
2044
2045<p><a name="upsp3"><h4>3.14.5 SP3 File - optional</h4></p>
2046<p>Specify a path for saving the generated orbit corrections as SP3 orbit files. If the specified directory does not exist, BNC will not create SP3 orbit files. The following is a path example for a Linux system:<br>/home/user/BNC${GPSWD}.sp3<br>Note that '${GPSWD}' produces the GPS Week and Day number in the file name.</p>
2047<p>
2048Default is an empty option field, meaning that you don't want BNC to save the uploaded stream contents in daily SP3 files.
2049</p>
2050<p>
2051As an SP3 file contents should be referred to the satellites Center of Mass (CoM) while Broadcast Corrections are referred to the satellites APC, an offset has to be applied which is available from an IGS ANTEX file (see section 'ANTEX File'). You should therefore specify the 'ANTEX File' path under tab 'PPP (2)' if you want to save the stream contents in SP3 format. If you don't specify an 'ANTEX File' path there, the SP3 file contents will be referred to the satellites APCs.
2052</p>
2053<p>
2054The file names for the daily SP3 files follow the convention for SP3 file names. The first three characters of each file name are set to 'BNC'. Note that clocks in the SP3 orbit files are not corrected for the conventional periodic relativistic effect.
2055</p>
2056<p>
2057In case the 'Combine Corrections' table contains only one Broadcast Corrections stream, BNC will merge that stream with Broadcast Ephemeris to save results in files specified here through SP3 and/or Clock RINEX file path. In such a case you have to define only the SP3 and Clock RINEX file path and no further option in the 'Upload Corrections' table.
2058</p>
2059
2060<p>
2061Note that BNC outputs a complete list of SP3 'Epoch Header Records' even if no 'Position and Clock Records' are available for certain epochs because of stream outages. Note further that the 'Number of Epochs' in the first SP3 header record may not be correct because that number is not available when the file is created. Depending on your processing software (e.g. Bernese GNSS Software, BSW) it could therefore be necessary to correct an incorrect 'Number of Epochs' in the file before you use in Post Processing.
2062</p>
2063
2064<p><a name="uprinex"><h4>3.14.6 RNX File - optional</h4></p>
2065<p>
2066The clock corrections generated by BNC for upload can be logged in Clock RINEX format. The file naming follows the RINEX convention.
2067</p>
2068<p>
2069Specify a path for saving the generated clock corrections as Clock RINEX files. If the specified directory does not exist, BNC will not create Clock RINEX files. The following is a path example for a Linux system:<br>/home/user/BNC${GPSWD}.clk<br>Note that '${GPSWD}' produces the GPS Week and Day number in the file name.
2070</p>
2071<p>
2072Note further that clocks in the Clock RINEX files are not corrected for the conventional periodic relativistic effect.
2073</p>
2074
2075<p><a name="upinter"><h4>3.14.7 Interval - mandatory if 'Upload Table' entries specified</h4></p>
2076<p>
2077Select the length of Clock RINEX files and SP3 Orbit files. The default value is 1 day.
2078</p>
2079
2080<p><a name="upclksmpl"><h4>3.14.8 Sampling - mandatory if 'Upload Table' entries specified</h4></p>
2081<p>BNC requires an orbit corrections sampling interval for the stream to be uploaded and sampling intervals for SP3 and Clock RINEX files. The outgoing stream's clock correction sampling interval follows that of incoming corrections and is therefore nothing to be specified here.</p>
2082
2083<p><a name="upclkorb"><h4>3.14.8.1 Orbits - mandatory if 'Upload Table' entries specified</h4></p>
2084<p>Select the stream's orbit correction sampling interval in seconds. A value of 60 sec may be appropriate.</p>
2085<p> A value of zero '0' tells BNC to upload all orbit correction samples coming in from the real-time GNSS engine along with the clock correction samples to produce combined orbit and clock corrections to Broadcast Ephemeris (1060 for GPS, 1066 for GLONASS).
2086</p>
2087
2088<p><a name="upclksp3"><h4>3.14.8.2 SP3 - mandatory if 'SP3 File' is specified</h4></p>
2089<p>Select the SP3 orbit file sampling interval in minutes. A value of 15 min may be appropriate. A value of zero '0' tells BNC to store all available samples into SP3 orbit files.</p>
2090
2091<p><a name="upclkrnx"><h4>3.14.8.3 RINEX - mandatory if 'RNX File' is specified</h4></p>
2092<p>Select the Clock RINEX file sampling interval in seconds. A value of 10 sec may be appropriate. A value of zero '0' tells BNC to store all available samples into Clock RINEX files.</p>
2093
2094<p><a name="upcustom"><h4>3.14.9 Custom Trafo - optional if 'Upload Table' entries specified</h4></p>
2095<p>Hit 'Custom Trafo' to specify your own 14 parameter Helmert Transformation instead of selecting a predefined transformation through 'System' button.</p>
2096
2097<p>
2098The following screenshot shows the encoding and uploading of a stream of precise orbits and clocks coming from a real-time engine in 'RTNET' ASCII format. The stream is uploaded to NTRIP Broadcaster 'products.igs-ip.net'. It is referred to APC and IGS08. Uploaded data are locally saved in SP3 and Clock RINEX format. The SSR Provider ID is set to 3. The SSR Solution ID is and the Issue of Data SSR are set to 1. Required Broadcast Ephemeris are received via stream 'RTCM3EPH'.
2099</p>
2100<p><img src="IMG/screenshot26.png"/></p>
2101<p><u>Figure 20:</u> Producing Broadcast Corrections from incoming precise orbits and clocks and uploading them to an NTRIP Broadcaster.</p>
2102
2103<p><a name="upeph"><h4>3.15. Upload Ephemeris</h4></p>
2104<p>
2105BNC can upload a stream carrying Broadcast Ephemeris in RTCM Version 3 format to an NTRIP Broadcaster.
2106</p>
2107
2108<p><a name="brdcserver"><h4>3.15.1 Host &amp; Port - optional</h4></p>
2109<p>
2110Specify the 'Host' IP name or number of an NTRIP Broadcaster to upload the stream. An empty option field means that you don't want to upload Broadcast Ephemeris.
2111</p>
2112<p>
2113Enter the NTRIP Broadcaster's IP 'Port' number for stream upload. Note that NTRIP Broadcasters are often configured to provide access on more than one port, usually
2114port 80 and 2101. If you experience communication problems on port 80, you should try to use the alternative port(s).
2115</p>
2116
2117<p><a name="brdcmount"><h4>3.15.2 Mountpoint &amp; Password - mandatory if 'Host' is set</h4></p>
2118<p>
2119BNC uploads a stream to the NTRIP Broadcaster by referring to a dedicated mountpoint that has been set by its operator. Specify the mountpoint based on the details you received for your stream from the operator. It is often a four character ID (capital letters) plus an integer number.</p>
2120<p>The stream upload may be protected through an upload 'Password'. Enter the password you received from the NTRIP Broadcaster operator along with the mountpoint.</p>
2121</p>
2122
2123<p><a name="brdcsmpl"><h4>3.15.3 Sampling - mandatory if 'Host' is set</h4></p>
2124Select the Broadcast Ephemeris repetition interval in seconds. Defaut is '5' meaning that a complete set of Broadcast Ephemeris is uploaded every 5 seconds.
2125</p>
2126
2127<p><img src="IMG/screenshot28.png"/></p>
2128<p><u>Figure 21:</u> Producing a Broadcast Ephemeris stream from navigation messages of globally distributed RTCM streams and uploading them in RTCM Version 3 format to an NTRIP Broadcaster.</p>
2129
2130<p><a name="streams"><h4>3.16. Streams</h4></p>
2131<p>
2132Each stream on an NTRIP Broadcaster (and consequently on BNC) is defined using a unique source ID called mountpoint. An NTRIP Client like BNC accesses the desired stream by referring to its mountpoint. Information about streams and their mountpoints is available through the source-table maintained by the NTRIP Broadcaster. Note that mountpoints could show up in BNC more than once when retrieving streams from several NTRIP Broadcasters.
2133</p>
2134
2135<p>
2136Streams selected for retrieval are listed under the 'Streams' canvas on BNC's main window. The list provides the following information either extracted from source-table(s) produced by the NTRIP Broadcasters or introduced by BNC's user:
2137</p>
2138<p>
2139<table>
2140<tr><td>'resource loader'&nbsp; </td><td>NTRIP Broadcaster URL and port, or<br>TCP/IP host and port, or<br>UDP port, or<br>Serial input port specification.</td></tr>
2141<tr><td>'mountpoint' &nbsp;</td><td>Mountpoint introduced by NTRIP Broadcaster, or<br>Mountpoint introduced by BNC's user.</td></tr>
2142<tr><td>'decoder' &nbsp;</td><td>Name of decoder used to handle the incoming stream content according to its format; editable.</td></tr>
2143<tr><td>'lat' &nbsp;</td><td>Approximate latitude of reference station, in degrees, north; editable if 'nmea' = 'yes'.</td></tr>
2144<tr><td>'long' &nbsp;</td><td>Approximate longitude of reference station, in degrees, east; editable if 'nmea' = 'yes'.</td></tr>
2145<tr><td>'nmea' &nbsp;</td><td>Indicates whether or not streaming needs to be initiated by BNC through sending NMEA-GGA message carrying position coordinates in 'lat' and 'long'.</td></tr>
2146<tr><td>'ntrip' &nbsp;</td><td>Selected NTRIP transport protocol version (1, 2, 2s, R, or U), or<br>'N' for TCP/IP streams without NTRIP, or<br>'UN' for UDP streams without NTRIP, or<br>'S' for serial input streams without NTRIP.</td></tr>
2147<tr><td>'bytes' &nbsp;</td><td>Number of bytes received.
2148</table>
2149</p>
2150
2151<p><a name="streamedit"><h4>3.16.1 Edit Streams</h4></p>
2152<ul>
2153<li>
2154BNC automatically allocates one of its internal decoders to a stream based on the stream's 'format' and 'format-details' as given in the source-table. However, there might be cases where you need to override the automatic selection due to incorrect source-table for example. BNC allows users to manually select the required decoder by editing the decoder string. Double click on the 'decoder' field, enter your preferred decoder and then hit Enter. The accepted decoder strings are 'RTCM_2.x', 'RTCM_3.x' and 'RTNET'.
2155</li>
2156<li>
2157In case you need to log the raw data as is, BNC allows users to by-pass its decoders and directly save the input in daily log files. To do this, specify the decoder string as 'ZERO'. The generated file names are created from the characters of the streams mountpoints plus two-digit numbers each for year, month, and day. Example: Setting the 'decoder' string for mountpoint WTZZ0 to 'ZERO' and running BNC on March 29, 2007 would save the raw data in a file named WTZZ0_070329.
2158</li>
2159<li>
2160BNC can also retrieve streams from virtual reference stations (VRS). To initiate these streams, an approximate rover position needs to be sent in NMEA format to the NTRIP Broadcaster. In return, a user-specific data stream is generated, typically by Network-RTK software. VRS streams are indicated by a 'yes' in the source-table as well as in the 'nmea' column on the 'Streams' canvas in BNC's main window. They are customized exactly to the latitude and longitude transmitted to the NTRIP Broadcaster via NMEA-GGA messages.
2161<br>If NMEA-GGA messages are not coming from a serial connected GNSS rover, BNC simulates them from the default latitude and longitude of the source-table as shown in the 'lat' and 'long' columns on the 'Streams' canvas. However, in most cases you would probably want to change these defaults according to your requirement. Double-click on 'lat' and 'long' fields, enter the values you wish to send and then hit Enter. The format is in positive north latitude degrees (e.g. for northern hemisphere: 52.436, for southern hemisphere: -24.567) and eastern longitude degrees (example: 358.872 or -1.128). Only streams with a 'yes' in their 'nmea' column can be edited. The position must preferably be a point within the VRS service area of the network. RINEX files generated from these streams will contain an additional COMMENT line in the header beginning with 'NMEA' showing the 'lat' and 'long' used.
2162<br>Note that when running BNC in a Local Area Network (LAN), NMEA strings may be blocked by a proxy server, firewall or virus scanner when not using the NTRIP Version 2 transport protocol..
2163</li>
2164</ul>
2165
2166<p><a name="streamdelete"><h4>3.16.2 Delete Stream</h4></p>
2167<p>
2168To remove a stream from the 'Streams' canvas in the main window, highlight it by clicking on it and hit the 'Delete Stream' button. You can also remove multiple streams simultaneously by highlighting them using +Shift and +Ctrl.</p>
2169
2170<p><a name="streamconf"><h4>3.16.3 Reconfigure Stream Selection On-the-fly</h4></p>
2171<p>
2172The streams selection can be changed on-the-fly without interrupting uninvolved threads in the running BNC process.
2173</p>
2174<p>
2175<u>Window mode:</u> Hit 'Save &amp; Reread Configuration' while BNC is in window mode and already processing data to let changes of your streams selection immediately become effective.
2176<p>
2177<u>No window mode:</u> When operating BNC online in 'no window' mode (command line option -nw), you force BNC to reread its 'mountPoints' configuration option from disk at pre-defined intervals. Select '1 min', '1 hour', or '1 day' as 'Reread configuration' option to reread the 'mountPoints' option every full minute, hour, or day. This lets a 'mountPoints' option edited in between in the configuration file become effective without terminating uninvolved threads. See annexed section 'Configuration Examples' for a configuration file example and a list of other on-the-fly changeable options.
2178</p>
2179
2180<p><a name="logs"><h4>3.17. Logging</h4></p>
2181<p>
2182A tabs section on the bottom of the main window provides online control of BNC's activities. Tabs are available to show the records saved in a logfile, for a plot to control the bandwidth consumption, for a plot showing stream latencies, and for time series plots of PPP results.
2183</p>
2184<p><a name="logfile"><h4>3.17.1 Log</h4></p>
2185<p>
2186Records of BNC's activities are shown in the 'Log' tab. They can be saved into a file when a valid path is specified in the 'Logfile (full path)' field.
2187</p>
2188
2189<p><a name="throughput"><h4>3.17.2 Throughput</h4></p>
2190<p>
2191The bandwidth consumption per stream is shown in the 'Throughput' tab in bits per second (bps) or kilo bits per second (kbps). The following figure shows an example for the bandwidth consumption of incoming streams.
2192</p>
2193
2194<p><img src="IMG/screenshot08.png"/></p>
2195<p><u>Figure 22:</u> Bandwidth consumption of incoming streams.</p>
2196
2197<p><a name="latency"><h4>3.17.3 Latency</h4></p>
2198<p>
2199The latency of observations in each incoming stream is shown in the 'Latency' tab in milliseconds or seconds. Streams not carrying observations (i.e. those providing only Broadcast Ephemeris messages) or having an outage are not considered here and shown in red color. Note that the calculation of correct latencies requires the clock of the host computer to be properly synchronized. The next figure shows an example for the latency of incoming streams.
2200</p>
2201
2202<p><img src="IMG/screenshot07.png"/></p>
2203<p><u>Figure 23:</u> Latency of incoming streams.</p>
2204
2205<p><a name="ppptab"><h4>3.17.4 PPP Plot</h4></p>
2206<p>
2207Precise Point Positioning time series of North (red), East (green) and Up (blue) coordinate components are shown in the 'PPP Plot' tab when a 'Origin' option is defined. Values are either referred to reference coordinates (if specified) or referred to the first estimated set of coordinate components. The time as given in format [hh:mm] refers to GPS Time. The sliding PPP time series window covers a period of 5 minutes. Note that it may take up to 30 seconds or more till the first PPP solutions becomes available. The following figure shows the screenshot of a PPP time series plot of North, East and Up coordinate components.
2208</p>
2209
2210<p><img src="IMG/screenshot13.png"/></p>
2211<p><u>Figure 24:</u> Time series plot of PPP session.</p>
2212
2213<p><a name="bottom"><h4>3.18. Bottom Menu Bar</h4></p>
2214<p>
2215The bottom menu bar allows to add or delete streams to BNC's configuration and to start or stop it. It also provides access to BNC's online help function. The 'Add Stream' button opens a window that allows user to select one of several input communication links, see figure below.
2216</p>
2217
2218<p><img src="IMG/screenshot06.png"/></p>
2219<p><u>Figure 25:</u> Steam input communication links.</p>
2220
2221<p><a name="streamadd"><h4>3.18.1 Add Stream - Coming from Caster</h4></p>
2222
2223<p>
2224Button 'Add Stream' &gt; 'Coming from Caster' then opens a window that allows user to select data streams from an NTRIP Broadcaster according to their mountpoints and show a distribution map of offered streams.
2225</p>
2226
2227<p><a name="streamhost"><h4>3.18.1.1 Caster Host and Port - mandatory</h4></p>
2228<p>
2229Enter the NTRIP Broadcaster host IP and port number. Note that EUREF and IGS operate NTRIP Broadcasters at <u>http://www.euref-ip.net/home</u>, <u>http://www.igs-ip.net/home</u>, <u>http://www.products.igs-ip.net/home</u> and <u>http://mgex.igs-ip.net/home</u>.
2230</p>
2231
2232<p><a name="streamtable"><h4>3.18.1.2 Casters Table - optional</h4></p>
2233<p>
2234It may be that you are not sure about your NTRIP Broadcasters host and port number or you are interested in other broadcaster installations operated elsewhere. Hit 'Show' for a table of known broadcasters maintained at <u>www.rtcm-ntrip.org/home</u>. A window opens which allows selecting a broadcaster for stream retrieval, see figure below.
2235</p>
2236</p>
2237<p><img src="IMG/screenshot04.png"/></p>
2238
2239<p><u>Figure 26:</u> Casters table.</p>
2240
2241<p><a name="streamuser"><h4>3.18.1.3 User and Password - mandatory for protected streams</h4></p>
2242<p>
2243Some streams on NTRIP Broadcasters may be restricted. Enter a valid 'User' ID and 'Password' for access to protected streams. Accounts are usually provided per NTRIP Broadcaster through a registration procedure. Register through <u>http://igs.bkg.bund.de/ntrip/registeruser</u> for access to protected streams from EUREF and IGS.
2244</p>
2245
2246<p><a name="gettable"><h4>3.18.1.4 Get Table</h4></p>
2247<p>
2248Use the 'Get Table' button to download the source-table from the NTRIP Broadcaster. Pay attention to data fields 'format' and 'format-details'. Keep in mind that BNC can only decode and convert streams that come in RTCM Version 2, RTCM Version 3, or RTNET format. For access to observations, Broadcast Ephemeris and Broadcast Corrections in RTCM format streams must contain a selection of appropriate message types as listed in the Annex, cf. data field 'format-details' for available message types and their repetition rates in brackets. Note that in order to produce RINEX Navigation files RTCM Version 3 streams containing message types 1019 (GPS) and 1020 (GLONASS) and 1045 (Galileo) are required. Select your streams line by line, use +Shift and +Ctrl when necessary. The figure below provides an example source-table.
2249</p>
2250<p>
2251The contents of data field 'nmea' tells you whether a stream retrieval needs to be initiated by BNC through sending an NMEA-GGA message carrying approximate position coordinates (virtual reference station).
2252</p>
2253<p>
2254Hit 'OK' to return to the main window. If you wish you can click on 'Add Stream' and repeat the process again to retrieve streams from different casters.
2255</p>
2256<p><img src="IMG/screenshot05.png"/></p>
2257<p><u>Figure 27:</u> Broadcaster source-table.</p>
2258
2259<p>Button 'Map' leads to the presentation of a map showing the distribution of streams offered through the downloaded source-table.</p>
2260
2261<p><a name="ntripv"><h4>3.18.1.5 NTRIP Version - mandatory</h4></p>
2262<p>
2263Some limitations and deficiencies of the NTRIP Version 1 stream transport protocol are solved in NTRIP Version 2. Improvements mainly concern a full HTTP compatibility in view of requirements coming from proxy servers. Version 2 is backwards compatible to Version 1. Options implemented in BNC are:
2264</p>
2265<p>
2266&nbsp; 1:&nbsp; NTRIP Version 1, TCP/IP.<br>
2267&nbsp; 2:&nbsp; NTRIP Version 2 in TCP/IP mode.<br>
2268&nbsp; 2s:&nbsp; NTRIP Version 2 in TCP/IP mode via SSL.<br>
2269&nbsp; R:&nbsp; NTRIP Version 2 in RTSP/RTP mode.<br>
2270&nbsp; U:&nbsp; NTRIP Version 2 in UDP mode.
2271</p>
2272<p>
2273If NTRIP Version 2 is supported by the broadcaster:
2274</p>
2275<ul>
2276<li>Try using option '2' if your streams are otherwise blocked by a proxy server operated in front of BNC.</li>
2277<li>Option 'R' or 'U' may be selected if latency is more important than completeness for your application. Note that the latency reduction is likely to be in the order of 0.5 sec or less. Note further that options 'R' (RTSP/RTP mode) and 'U' (UDP mode) are not accepted by proxy servers and a mobile Internet Service Provider may not support it.</li>
2278</ul>
2279<p>
2280Select option '1' if you are not sure whether the broadcaster supports NTRIP Version 2.</li>
2281</p>
2282
2283<p><a name="map"><h4>3.18.1.6 Map - optional</h4></p>
2284<p>
2285Button 'Map' opens a window to show a distribution map of the caster's streams. You may like to zoom in or out using option 'Zoom +' or 'Zoom -'. You may also like to 'Clean' or 'Reset' a map or let it 'Fit' exactly to the current size of the window. Option 'Close' shuts the window.
2286</p>
2287<p><img src="IMG/screenshot24.png"/></p>
2288<p><u>Figure 28:</u> Stream distribution map derived from NTRIP Broadcaster source-table.</p>
2289
2290<p><a name="streamip"><h4>3.18.2 Add Stream - Coming from TCP/IP Port</h4></p>
2291<p>
2292Button 'Add Stream' &gt; 'Coming from TCP/IP Port' allows to retrieve streams via TCP directly from an IP address without using the NTRIP transport protocol. For that you:
2293<ul>
2294<li>Enter the IP address of the stream providing host.</li>
2295<li>Enter the IP port number of the stream providing host.</li>
2296<li>Specify a mountpoint. Recommended is a 4-character station ID. Example: FFMJ</li>
2297<li>Specify the stream format. Available options are 'RTCM_2', 'RTCM_3', 'RTNET', and 'ZERO'.</li>
2298<li>Enter the approximate latitude of the stream providing rover in degrees. Example: 45.32.</li>
2299<li>Enter the approximate longitude of the stream providing rover in degrees. Example: -15.20.</li>
2300</ul>
2301</p>
2302<p>
2303Streams directly received from a TCP/IP port show up with an 'N' for 'No NTRIP' in the 'Streams' canvas on BNC's main window. Latitude and longitude are to be entered just for informal reasons.
2304<p>
2305</p>
2306Note that this option works only if no proxy server is involved in the communication link.
2307</p>
2308
2309<p><a name="streamudp"><h4>3.18.3 Add Stream - Coming from UDP Port</h4></p>
2310<p>
2311Button 'Add Stream' &gt; 'Coming from UDP Port' allows to pick up streams arriving directly at one of the local host's UDP ports without using the NTRIP transport protocol. For that you:
2312<ul>
2313<li>Enter the local port number where the UDP stream arrives.</li>
2314<li>Specify a mountpoint. Recommended is a 4-character station ID. Example: FFMJ</li>
2315<li>Specify the stream format. Available options are 'RTCM_2', 'RTCM_3', 'RTNET', and 'ZERO'.</li>
2316<li>Enter the approximate latitude of the stream providing rover in degrees. Example: 45.32.</li>
2317<li>Enter the approximate longitude of the stream providing rover in degrees. Example: -15.20.</li>
2318</ul>
2319</p>
2320<p>
2321Streams directly received at a UDP port show up with a 'UN' for 'UDP, No NTRIP' in the 'Streams' canvas section on BNC's main window. Latitude and longitude are to be entered just for informal reasons.
2322<p>
2323
2324<p><a name="streamser"><h4>3.18.4 Add Stream - Coming from Serial Port</h4></p>
2325<p>
2326Button 'Add Stream' &gt; 'Coming from Serial Port' allows to retrieve streams from a GNSS receiver via serial port without using the NTRIP transport protocol. For that you:
2327<ul>
2328<li>Specify a mountpoint. Recommended is a 4-character station ID. Example: FFMJ</li>
2329<li>Specify the stream format. Available options are 'RTCM_2', 'RTCM_3', 'RTNET', and 'ZERO'.</li>
2330<li>Enter the approximate latitude of the stream providing receiver in degrees. Example: 45.32.</li>
2331<li>Enter the approximate longitude of the stream providing receiver in degrees. Example: -15.20.</li>
2332<li>Enter the serial 'Port name' selected on your host for communication with the receiver. Valid port names are
2333<pre>
2334Windows: COM1, COM2
2335Linux: /dev/ttyS0, /dev/ttyS1
2336FreeBSD: /dev/ttyd0, /dev/ttyd1
2337Digital Unix: /dev/tty01, /dev/tty02
2338HP-UX: /dev/tty1p0, /dev/tty2p0
2339SGI/IRIX: /dev/ttyf1, /dev/ttyf2
2340SunOS/Solaris: /dev/ttya, /dev/ttyb
2341</pre>
2342</li>
2343<li>Select a 'Baud rate' for the serial input. Note that using a high baud rate is recommended.</li>
2344<li>Select the number of 'Data bits' for the serial input. Note that often '8' data bits are used.</li>
2345<li>Select the 'Parity' for the serial input. Note that parity is often set to 'NONE'.</li>
2346<li>Select the number of 'Stop bits' for the serial input. Note that often '1' stop bit is used.</li>
2347<li>Select a 'Flow control' for the serial link. Select 'OFF' if you don't know better.</li>
2348</ul>
2349</p>
2350<p>
2351When selecting one of the serial communication options listed above, make sure that you pick those configured to the serial connected GNSS receiver.
2352</p>
2353
2354<p>
2355Streams received from a serial connected GNSS receiver show up with an 'S' (for <u>S</u>erial Port, no NTRIP) in the 'Streams' canvas section on BNC's main window. Latitude and longitude are to be entered just for informal reasons.
2356<p>
2357
2358<p>
2359The following figure shows a BNC example setup for pulling a stream via serial port on a Linux operating system.
2360</p>
2361<p><img src="IMG/screenshot15.png"/></p>
2362<p><u>Figure 29:</u> BNC setup for pulling a stream via serial port.</p>
2363
2364<p><a name="start"><h4>3.18.5 Start</h4></p>
2365<p>
2366Hit 'Start' to start retrieving, decoding or converting GNSS data streams in real-time. Note that 'Start' generally forces BNC to begin with fresh RINEX which might overwrite existing files when necessary unless the option 'Append files' is ticked.
2367</p>
2368
2369<p><a name="stop"><h4>3.18.6 Stop</h4></p>
2370<p>
2371Hit the 'Stop' button in order to stop BNC.
2372</p>
2373
2374<p><a name="cmd"><h4>3.19. Command Line Options</h4></p>
2375<p>
2376Command line options are available to run BNC in 'no window' mode or let it read data offline from one or several files for debugging or Post Processing purposes. BNC will then use processing options from the involved configuration file. Note that the self-explaining contents of the configuration file can easily be edited. It is possible to introduce a specific configuration file name instead of using the default name 'BNC.bnc'.
2377</p>
2378
2379<p><a name="nw"><h4>3.19.1 No Window Mode - optional</h4></p>
2380<p>
2381Apart from its regular windows mode, BNC can be started on all systems as a batch job with command line option '-nw'. BNC will then run in 'no window' mode, using processing options from its configuration file on disk. Terminate BNC using Windows Task Manager when running it in 'no window' mode on Windows systems.
2382</p>
2383<p>
2384Example:<br><br>
2385bnc.exe -nw
2386</p>
2387<p>
2388It is obvious that BNC requires graphics support when started in interactive
2389mode. But, note that it also requires graphics support when producing plots in
2390batch mode (option -nw). Windows and Mac systems always support graphics. For
2391producing plots in batch mode on Linux systems you must make sure that at
2392least a virtual X-Server such as 'Xvfb' is installed and the '-display' option
2393is used. The following is an example shell script to execute BNC in batch mode
2394for producing multipath plots from RINEX files. It could be used via 'crontab':
2395</p>
2396<pre>
2397#!/bin/bash
2398
2399# Save string localhost
2400echo "localhost" > /home/user/hosts
2401
2402# Start virtual X-Server, save process ID
2403/usr/bin/Xvfb :29 -auth /home/user/hosts -screen 0 1280x1024x8 &
2404psID=`echo $!`
2405
2406# Run BNC application with defined display variable
2407/home/user/BNC/bnc --conf /dev/null --key reqcAction Analyze --key reqcObsFile ons12090.12o --key reqcNavFile brdc2090.12p --key reqcOutLogFile multi.txt --key reqcPlotDir /home/user --display localhost:29 --nw
2408
2409# BNC done, kill X-server process
2410kill $psID
2411</pre>
2412
2413<p><a name="post"><h4>3.19.2 File Mode - optional</h4></p>
2414<p>
2415Although BNC is primarily a real-time online tool, for debugging purposes it can be run offline to read data from a file previously saved through option 'Raw output file'. Enter the following command line option for that
2416</p>
2417<p>
2418--file &lt;<u>inputFileName</u>&gt;
2419</p>
2420
2421and specify the full path to an input file containing previously saved data. Example:<br><br>
2422./bnc --file /home/user/raw.output_110301
2423</p>
2424<p>
2425Note that when running BNC offline, it will use options for file saving, interval, sampling, PPP etc. from its configuration file.
2426</p>
2427<p>Note further that option '--file' forces BNC to appy the '-nw' option for running in 'no window' mode.
2428</p>
2429
2430<p><a name="conffile"><h4>3.19.3 Configuration File - optional</h4></p>
2431The default configuration file name is 'BNC.bnc'. You may change this name at startup time using the command line option '--conf &lt;<u>confFileName</u>&gt;'. This allows running several BNC jobs in parallel on the same host using different sets of configuration options. <u>confFileName</u> stands either for the full path to a configuration file or just for a file name. If you introduce only a filename, the corresponding file will be saved in the current working directory from where BNC is started.
2432</p>
2433<p>
2434Example:<br><br>
2435./bnc --conf MyConfig.bnc
2436</p>
2437<p>
2438This leads to a BNC job using configuration file 'MyConfig.bnc'. The configuration file will be saved in the current working directory.
2439</p>
2440
2441<p><a name="confopt"><h4>3.19.4 Configuration Options - optional</h4></p>
2442<p>
2443BNC applies options from the configuration file but allows updating every one of them on the command line while the contents of the configuration file remains unchanged. The command line syntax for that looks as follows
2444</p>
2445<p>
2446--key &lt;keyName&gt; &lt;keyValue&gt;
2447</p>
2448<p>
2449where &lt;keyName&gt; stands for the name of an option contained in the configuration file and &lt;keyValue&gt; stands for the value you want to assign to it. The following is a syntax example for a complete command line:
2450</p>
2451<p>
2452bnc --nw --conf &lt;confFileName&gt --key &lt;keyName1&gt; &lt;keyValue1&gt; --key &lt;keyName2&gt; &lt;keyValue2&gt; ...
2453</p>
2454<p>
2455Example:
2456</p>
2457<p>
2458./bnc --conf CONFIG.bnc --key proxyPort 8001 --key rnxIntr "1 day"
2459</p>
2460
2461<p><a name="limits"><h3>4. Limitations</h3></p>
2462<ul>
2463<li>
2464In Qt-based desktop environments (like KDE) on Unix/Linux platforms it may happen that you experience a crash of BNC at startup even when running the program in the background using the '-nw' option. This is a known bug most likely resulting from an incompatibility of Qt libraries in the environment and in BNC. Entering the command 'unset SESSION_MANAGER' before running BNC may help as a work-around.
2465</li>
2466
2467<li>
2468Using RTCM Version 3 to produce RINEX files, BNC will properly handle most message types. However, when handling message types 1001, 1003, 1009 and 1011 where the ambiguity field is not set, the output will be no valid RINEX. All values will be stored modulo 299792.458 (speed of light).
2469</li>
2470<li>
2471Using RTCM Version 2, BNC will only handle message types 18 and 19 or 20 and 21 together with position and the antenna offset information carried in types 3 and 22. Note that processing carrier phase corrections and pseudo-range corrections contained in message types 20 and 21 needs access to Broadcast Ephemeris. Hence, whenever dealing with message types 20 and 21, make sure that Broadcast Ephemeris become available for BNC through also retrieving at least one RTCM Version 3 stream carrying message types 1019 (GPS ephemeris) and 1020 (GLONASS ephemeris).
2472</li>
2473<li>
2474BNC's 'Get Table' function only shows the STR records of a source-table. You can use an Internet browser to download the full source-table contents of any NTRIP Broadcaster by simply entering its URL in the form of <u>http://host:port</u>. Data field number 8 in the NET records may provide information about where to register for an NTRIP Broadcaster account.
2475</li>
2476<li>
2477EUREF as well as IGS adhere to an open data policy. Streams are made available through NTRIP Broadcasters at <u>www.euref-ip.net</u>, <u>www.igs-ip.net</u> and <u>products.igs-ip.net</u> free of charge to anyone for any purpose. There is no indication up until now how many users will need to be supported simultaneously. The given situation may develop in such a way that it might become difficult to serve all registered users at the same times. In cases where limited resources on the NTRIP Broadcaster side (software restrictions, bandwidth limitation etc.) dictates, first priority in stream provision will be given to stream providers followed by re-broadcasting activities and real-time analysis centers while access to others might be temporarily denied.
2478</li>
2479<li>
2480Once BNC has been started, many of its configuration options cannot be changed as long as it is stopped. See chapter 'Reread Configuration' for on-the-fly configuration exceptions.
2481</li>
2482</ul>
2483
2484<p><a name="annex"><h3>5. Annex</h3></p>
2485<p>
24865.1. <a href=#history>Revision History</a><br>
24875.2. <a href=#rtcm>RTCM</a><br>
2488&nbsp; &nbsp; &nbsp; 5.2.1 NTRIP <a href=#ntrip1>Version 1</a><br>
2489&nbsp; &nbsp; &nbsp; 5.2.2 NTRIP <a href=#ntrip2>Version 2</a><br>
2490&nbsp; &nbsp; &nbsp; 5.2.3 RTCM <a href=#rtcm2>Version 2</a><br>
2491&nbsp; &nbsp; &nbsp; 5.2.4 RTCM <a href=#rtcm3>Version 3</a><br>
24925.3. <a href=#config>Configuration Examples</a><br>
24935.4. <a href=#links>Further Reading</a>
2494</p>
2495
2496<p><a name=history><h4>5.1 Revision History</h3></p>
2497<table>
2498<tr></tr>
2499
2500<tr>
2501<td>Dec 2006 &nbsp;</td><td>Version 1.0b &nbsp;</td>
2502<td>[Add] First Beta Binaries published based on Qt 4.2.3.</td>
2503</tr>
2504
2505<tr>
2506<td>Jan 2007 &nbsp;</td><td>Version 1.1b &nbsp;</td>
2507<td>[Add] Observables C2, S1, and S2<br>[Add] Virtual reference station access<br>[Bug] RTCM2 decoder time tag fixed<br>[Mod] Small letters for public RINEX skeleton files<br>[Add] Online help through Shift+F1</td>
2508</tr>
2509
2510<tr>
2511<td>Apr 2007 &nbsp;</td><td>Version 1.2b &nbsp;</td>
2512<td>[Bug] Output only through IP port<br>[Bug] Method 'reconnecting' now thread-save<br> [Add] ZERO decoder added<br> [Mod] Download public RINEX skeletons once per day<br> [Mod] Upgrade to Qt Version 4.2.3<br> [Mod] Replace 'system' call for RINEX script by 'QProcess'<br> [Add] HTTP Host directive for skeleton file download<br> [Add] Percent encoding for user IDs and passwords<br> [Bug] Exit execution of calling thread for RTCM3 streams<br> [Bug] Signal-slot mechanism for threads</td>
2513</tr>
2514
2515<tr>
2516<td>May 2007 &nbsp;</td><td>Version 1.3 &nbsp;</td>
2517<td>[Add] Source code published.</td>
2518</tr>
2519
2520<tr>
2521<td>Jul 2007 &nbsp;</td><td>Version 1.4 &nbsp;</td>
2522<td>[Bug] Skip messages from proxy server<br> [Bug] Call RINEX script through 'nohup'</td>
2523</tr>
2524
2525<tr>
2526<td>Apr 2008 &nbsp;</td><td>Version 1.5 &nbsp;</td>
2527<td>[Add] Handle ephemeris from RTCM Version 3 streams<br> [Add] Upgrade to Qt Version 4.3.2<br> [Add] Optional RINEX v3 output<br> [Add] SBAS support<br> [Bug] RINEX skeleton download following stream outage<br> [Add] Handle ephemeris from RTIGS streams<br> [Add] Monitor stream failure/recovery and latency<br> [Mod] Redesign of main window<br> [Bug] Freezing of About window on Mac systems<br> [Bug] Fixed problem with PRN 32 in RTCMv2 decoder<br> [Bug] Fix for Trimble 4000SSI receivers in RTCMv2 decoder<br> [Mod] Major revision of input buffer in RTCMv2 decoder</td>
2528</tr>
2529
2530<tr>
2531<td>Dec 2008 &nbsp;</td><td>Version 1.6 &nbsp;</td>
2532<td>[Mod] Fill blank columns in RINEXv3 with 0.000<br> [Add] RTCMv3 decoder for clock and orbit corrections<br>[Add] Check RTCMv3 streams for incoming message types<br> [Add] Decode RTCMv2 message types 3, 20, 21, and 22<br> [Add] Loss of lock and lock time indicator<br> [Bug] Rounding error in RTCMv3 decoder concerning GLONASS height<br> [Mod] Accept GLONASS in RTCMv3 when transmitted first<br> [Add] Leap second 1 January 2009<br> [Add] Offline mode, read data from file<br> [Add] Output antenna descriptor, coordinates and eccentricities from RTCMv3<br> [Add] Reconfiguration on-the-fly<br> [Mod] Binary output of synchronized observations<br> [Add] Binary output of unsynchronized observations<br> [Bug] Fixed problem with joined RTCMv3 blocks</td>
2533</tr>
2534
2535<tr>
2536<td>Dec 2008 &nbsp;</td><td>Version 1.6.1 &nbsp;</td>
2537<td>[Mod] HTTP GET when no proxy in front</td>
2538</tr>
2539
2540<tr>
2541<td>Nov 2009 &nbsp;</td><td>Version 1.7 &nbsp;</td>
2542<td>[Bug] RINEX Navigation file format<br> [Add] Upgrade to Qt Version 4.5.2<br> [Add] Support of NTRIP v2<br> [Add] Rover support via serial port<br> [Add] Show broadcaster table from www.rtcm-ntrip.org<br> [Add] Enable/disable tab widgets<br> [Add] User defined configuration file name<br> [Mod] Switch to configuration files in ini-Format<br> [Add] Daily logfile rotation<br> [Add] Read from TCP/IP port, by-pass NTRIP transport protocol<br> [Add] Save NMEA messages coming from rover<br> [Add] Auto start<br> [Add] Drag and drop ini files<br> [Add] Read from serial port, by-pass NTRIP transport protocol<br> [Mod] Update of SSR messages following RTCM 091-2009-SC104-542<br> [Add] Read from UPD port, by-pass NTRIP transport protocol<br> [Mod] Output format of Broadcast Corrections<br> [Add] Throughput plot<br> [Add] Latency plot</td>
2543</tr>
2544
2545<tr>
2546<td>Nov 2009 &nbsp;</td><td>Version 1.8 &nbsp;</td>
2547<td>[Mod] On-the-fly reconfiguration of latency and throughput plots</td>
2548</tr>
2549
2550<tr>
2551<td>Feb 2010 &nbsp;</td><td>Version 2.0 &nbsp;</td>
2552<td>[Mod] Change sign of Broadcast Corrections<br> [Add] Real-time PPP option</td>
2553</tr>
2554
2555<tr>
2556<td>Jun 2010 &nbsp;</td><td>Version 2.1 &nbsp;</td>
2557<td>[Bug] SSR GLONASS message generation<br> [Add] PPP in Post Processing mode<br> [Mod] Update of SSR messages following draft dated 2010-04-12<br> [Mod] Generating error message when observation epoch is wrong</td>
2558</tr>
2559
2560<tr>
2561<td>Jul 2010 &nbsp;</td><td>Version 2.2 &nbsp;</td>
2562<td>[Bug] GLONASS ephemeris time</td>
2563</tr>
2564
2565<tr>
2566<td>Aug 2010 &nbsp;</td><td>Version 2.3 &nbsp;</td>
2567<td>[Mod] Internal format for saving raw streams<br> [Bug] Outlier detection in GLONASS ambiguity resolution<br> [Mod] Format of PPP logs in logfile<br> [Bug] Complete acceleration terms for GLONASS ephemeris<br> [Bug] Handling ephemeris IOD's in PPP mode</td>
2568</tr>
2569
2570<tr>
2571<td>Dec 2010 &nbsp;</td><td>Version 2.4 &nbsp;</td>
2572<td>[Add] Output of averaged positions when in PPP mode<br> [Mod] Use always the latest received set of Broadcast Ephemeris<br> [Add] QuickStart PPP option<br> [Mod] Improvement of data sharing efficiency among different threads<br> [Mod] Design of PPP tab section<br> [Add] Sigmas for observations and parameters<br> [Add] Stream distribution map<br> [Bug] GPS Ephemeris in RINEX v3 format</td>
2573</tr>
2574
2575<tr>
2576<td>Feb 2011 &nbsp;</td><td>Version 2.5 &nbsp;</td>
2577<td>[Add] PPP option for sync of clock observations and corrections<br> [Add] Drafted RTCMv3 Galileo ephemeris messages 1045<br> [Add] Drafted RTCMv3 Multiple Signal Messages<br> [Add] Optional specification of sigmas for coordinates and troposphere in PPP<br> [Add] Include Galileo in SPP<br> [Add] Include Galileo observations in output via IP port<br> [Add] Include Galileo observations in output via RINEXv3 files<br> [Mod] Interface format for feeding a real-time engine with observations<br> [Add] Correct observations for antenna phase center offsets<br> [Add] Combine orbit/clock correction streams<br> [Add] Specify corrections mountpoint in PPP tab</td>
2578</tr>
2579
2580<tr>
2581<td>Apr 2011 &nbsp;</td><td>Version 2.6 &nbsp;</td>
2582<td>[Add] Complete integration of BNS in BNC<br> [Add] SP3 and Clock RINEX output<br> [Add] PPP in Post Processing Mode<br> [Add] Some RINEX editing & QC functionality<br> [Add] Threshold for orbit outliers in combination solution<br> [Add] Real-time engine becomes orbit/clock server instead of client<br> [Mod] 'EOE' added to orbit/clock stream from engine<br> [Add] Correction for antenna eccentricities<br> [Add] Quick start mode for PPP<br> [Mod] Design of format for feeding engine changed to follow RINEX v3<br> [Mod] Implementation of SSR message encoding modified according to standard<br> [Add] SSL/TLS Support of NTRIP Version 2<br> [Mod] Switch to Qt version 4.7.3<br> [Add] RINEX editing, concatenation and quality check<br> [Add] Reading all configuration options from command line<br> [Mod] RTCMv3 Galileo Broadcast Ephemeris message 1045<br> [Mod] Change default configuration file suffix from 'ini' to 'bnc'<br> [Add] Specific rates for orbits and clocks in streams and SP3/RNX files</td>
2583</tr>
2584
2585<tr>
2586<td>May 2012 &nbsp;</td><td>Version 2.6 &nbsp;</td>
2587<td>[Add] Version 2.6 published</td>
2588</tr>
2589
2590<tr>
2591<td>Aug 2012 &nbsp;</td><td>Version 2.7 &nbsp;</td>
2592<td>[Bug] Bug in L5 decoding fixed<br> [Bug] Bug in on-the-fly configuration fixed<br> [Add] Clock RINEX file header extended<br> [Add] Decoding/converting COMPASS and QZSS added<br> [Add] Work on RINEX v2 and v3 quality check started<br> [Mod] Source code completely re-arranged<br> [Add] QWT and QWTPOLAR graphics libraries added<br> [Add] RINEX v2 and v3 quality check through multipath analysis and sky plot<br> [Bug] Short periodic outages in PPP time series when operated when 'Sync Corr' set to zero<br> |Add] Log observation types contained in RTCM Version 3 MSM streams<br> [Add] Reading RINEX v3 observation type header records from RINEX skeleton files<br> [Add] Logfile for RINEX file editing and concatenation<br>[Add] Save PNG plot files on disk<br> [Add] Version 2.7 published</td>
2593</tr>
2594
2595</table>
2596</p>
2597
2598<p><a name="rtcm"><h4>5.2. RTCM</h4></p>
2599
2600<p>
2601The Radio Technical Commission for Maritime Services (RTCM) is an international non-profit scientific, professional and educational organization. Special Committees provide a forum in which governmental and non-governmental members work together to develop technical standards and consensus recommendations in regard to issues of particular concern. RTCM is engaged in the development of international standards for maritime radionavigation and radiocommunication systems. The output documents and reports prepared by RTCM Committees are published as RTCM Recommended Standards. Topics concerning Differential Global Navigation Satellite Systems (DGNSS) are handled by the Special Committee SC 104.
2602<p>
2603Personal copies of RTCM Recommended Standards can be ordered through <u>http://www.rtcm.org/orderinfo.php</u>.
2604</p>
2605
2606<p><a name="ntrip1"><h4>5.2.1 NTRIP Version 1</h4></p>
2607
2608<p>
2609'Networked Transport of RTCM via Internet Protocol' Version 1.0 (NTRIP) stands for an application-level protocol streaming Global Navigation Satellite System (GNSS) data over the Internet. NTRIP is a generic, stateless protocol based on the Hypertext Transfer Protocol HTTP/1.1. The HTTP objects are enhanced to GNSS data streams.
2610</p>
2611
2612<p>
2613NTRIP Version 1 is an RTCM standard designed for disseminating differential correction data (e.g. in the RTCM-104 format) or other kinds of GNSS streaming data to stationary or mobile users over the Internet, allowing simultaneous PC, Laptop, PDA, or receiver connections to a broadcasting host. NTRIP supports wireless Internet access through Mobile IP Networks like GSM, GPRS, EDGE, or UMTS.
2614</p>
2615
2616<p>
2617NTRIP is implemented in three system software components: NTRIP Clients, NTRIP Servers and NTRIP Broadcasters. The NTRIP Broadcaster is the actual HTTP server program whereas NTRIP Client and NTRIP Server are acting as HTTP clients.
2618</p>
2619
2620<p>
2621NTRIP is an open none-proprietary protocol. Major characteristics of NTRIP's dissemination technique are:
2622<ul>
2623<li>Based on the popular HTTP streaming standard; comparatively easy to implement when having limited client and server platform resources available.</li>
2624<li>Application not limited to one particular plain or coded stream content; ability to distribute any kind of GNSS data.</li>
2625<li>Potential to support mass usage; disseminating hundreds of streams simultaneously for thousands of users possible when applying modified Internet Radio broadcasting software.</li>
2626<li>Considering security needs; stream providers and users don't necessarily get into contact, streams often not blocked by firewalls or proxy servers protecting Local Area Networks.</li>
2627<li>Enables streaming over mobile IP networks because of using TCP/IP.</li>
2628</ul>
2629</p>
2630
2631<p>
2632The NTRIP Broadcaster maintains a source-table containing information on available NTRIP streams, networks of NTRIP streams and NTRIP Broadcasters. The source-table is sent to an NTRIP Client on request. Source-table records are dedicated to one of the following: Data Streams (record type STR), Casters (record type CAS), or Networks of streams (record type NET).
2633</p>
2634
2635<p>
2636Source-table records of type STR contain the following data fields: 'mountpoint', 'identifier', 'format', 'format-details', 'carrier', 'nav-system', 'network', 'country', 'latitude', 'longitude', 'nmea', 'solution', 'generator', 'compr-encryp', 'authentication', 'fee', 'bitrate', 'misc'.
2637</p>
2638<p>
2639Source-table records of type NET contain the following data fields: 'identifiey', 'operator', 'authentication', 'fee', 'web-net', 'web-str', 'web-reg', 'misc'.
2640</p>
2641<p>
2642Source-table records of type CAS contain the following data fields: 'host', 'port', 'identifier', 'operator', 'nmea', 'country', 'latitude', 'longitude', 'misc'.
2643</p>
2644
2645<p><a name="ntrip2"><h4>5.2.2 NTRIP Version 2</h4></p>
2646
2647<p>
2648The major changes of NTRIP Version 2 compared to Version 1.0 are:
2649</p>
2650
2651<ul>
2652<li>cleared and fixed design problems and HTTP protocol violations;</li>
2653<li>replaced non standard directives;</li>
2654<li>chunked transfer encoding;</li>
2655<li>improvements in header records;</li>
2656<li>source-table filtering;</li>
2657<li>RTSP communication.</li>
2658</ul>
2659
2660<p>NTRIP Version 2 allows to either communicate in TCP/IP mode or in RTSP/RTP mode or in UDP mode whereas Version 1 is limited to TCP/IP only. It furthermore allows using the Transport Layer Security (TLS) and its predecessor, Secure Sockets Layer (SSL) cryptographic protocols for secure NTRIP communication over the Internet.
2661</p>
2662
2663<p><a name="rtcm2"><h4>5.2.3 RTCM Version 2</h4></p>
2664<p>
2665Transmitting GNSS carrier phase data can be done through RTCM Version 2 messages. Please note that only RTCM Version 2.2 and 2.3 streams may include GLONASS data. Messages that may be of interest here are:
2666</p>
2667
2668<ul>
2669<li>
2670Type 1 message is the range correction message and is the primary message in code-phase differential positioning (DGPS). It is computed in the base receiver by computing the error in the range measurement for each tracked SV.
2671</li>
2672<li>
2673Type 2 message is automatically generated when a new set of satellite ephemeris is downloaded to the base receiver. It is the computed difference between the old ephemeris and the new ephemeris. Type 2 messages are used when the base station is transmitting Type 1 messages.
2674</li>
2675<li>
2676Type 3 and 22 messages are the base station position and the antenna offset. Type 3 and 22 are used in RTK processing to perform antenna reduction.
2677</li>
2678<li>
2679Type 6 message is a null frame filler message that is provided for data links that require continuous transmission of data, even if there are no corrections to send. As many Type 6 messages are sent as required to fill in the gap between two correction messages (type 1). Message 6 is not sent in burst mode.
2680</li>
2681<li>
2682Type 9 message serves the same purpose as Type 1, but does not require a complete satellite set. As a result, Type 9 messages require a more stable clock than a station transmitting Type 1 's, because the satellite corrections have different time references.
2683</li>
2684<li>
2685Type 16 message is simply a text message entered by the user that is transmitted from the base station to the rover. It is used with code-phase differential.
2686</li>
2687<li>
2688Type 18 and 20 messages are RTK uncorrected carrier phase data and carrier phase corrections.
2689</li>
2690<li>
2691Type 19 and 21 messages are the uncorrected pseudo-range measurements and pseudo-range corrections used in RTK.
2692</li>
2693<li>
2694Type 23 message provides the information on the antenna type used on the reference station.
2695</li>
2696<li>
2697Type 24 message carries the coordinates of the installed antenna's ARP in the GNSS coordinate system coordinates.
2698</li>
2699</ul>
2700
2701<p><a name="rtcm3"><h4>5.2.4 RTCM Version 3</h4></p>
2702<p>
2703RTCM Version 3 has been developed as a more efficient alternative to RTCM Version 2. Service providers and vendors have asked for a standard that would be more efficient, easy to use, and more easily adaptable to new situations. The main complaint was that the Version 2 parity scheme was wasteful of bandwidth. Another complaint was that the parity is not independent from word to word. Still another was that even with so many bits devoted to parity, the actual integrity of the message was not as high as it should be. Plus, 30-bit words are awkward to handle. The Version 3 standard is intended to correct these weaknesses.
2704</p>
2705<p>
2706RTCM Version 3 defines a number of message types. Messages that may be of interest here are:
2707<ul>
2708<li>Type 1001, GPS L1 code and phase.</li>
2709<li>Type 1002, GPS L1 code and phase and ambiguities and carrier to noise ratio.</li>
2710<li>Type 1003, GPS L1 and L2 code and phase.</li>
2711<li>Type 1004, GPS L1 and L2 code and phase and ambiguities and carrier to noise ratio.</li>
2712<li>Type 1005, Station coordinates XYZ for antenna reference point.</li>
2713<li>Type 1006, Station coordinates XYZ for antenna reference point and antenna height.</li>
2714<li>Type 1007, Antenna descriptor and ID.</li>
2715<li>Type 1008, Antenna serial number.</li>
2716<li>Type 1009, GLONASS L1 code and phase.</li>
2717<li>Type 1010, GLONASS L1 code and phase and ambiguities and carrier to noise ratio.</li>
2718<li>Type 1011, GLONASS L1 and L2 code and phase.</li>
2719<li>Type 1012, GLONASS L1 and L2 code and phase and ambiguities and carrier to noise ratio.</li>
2720<li>Type 1013, Modified julian date, leap second, configured message types and interval.</li>
2721<li>Type 1014 and 1017, Network RTK (MAK) messages (under development).</li>
2722<li>Type 1019, GPS ephemeris.</li>
2723<li>Type 1020, GLONASS ephemeris.</li>
2724<li>Type 4088 and 4095, Proprietary messages (under development).
2725</li>
2726</ul>
2727</p>
2728
2729<p>
2730The following is proposed Galileo Navigation Message under discussion for standardization:
2731<ul>
2732<li>Type 1045, Galileo ephemeris.</li>
2733</ul>
2734</p>
2735
2736<p>
2737The following are so-called 'State Space Representation' (SSR) messages:
2738<ul>
2739<li>Type 1057, GPS orbit corrections to Broadcast Ephemeris</li>
2740<li>Type 1058, GPS clock corrections to Broadcast Ephemeris</li>
2741<li>Type 1059, GPS code biases</li>
2742<li>Type 1060, Combined orbit and clock corrections to GPS Broadcast Ephemeris</li>
2743<li>Type 1061, GPS User Range Accuracy (URA)</li>
2744<li>Type 1062, High-rate GPS clock corrections to Broadcast Ephemeris<br><br></li>
2745<li>Type 1063, GLONASS orbit corrections to Broadcast Ephemeris</li>
2746<li>Type 1064, GLONASS clock corrections to Broadcast Ephemeris</li>
2747<li>Type 1065, GLONASS code biases</li>
2748<li>Type 1066, Combined orbit and clock corrections to GLONASS Broadcast Ephemeris</li>
2749<li>Type 1067, GLONASS User Range Accuracy (URA)</li>
2750<li>Type 1068, High-rate GLONASS clock corrections to Broadcast Ephemeris</li>
2751</ul>
2752</p>
2753
2754
2755<p>
2756The following are proposed 'Multiple Signal Messages' (MSM) under discussion for standardization:
2757<ul>
2758<li>Type 1071, Compact GPS pseudo-ranges</li>
2759<li>Type 1072, Compact GPS carrier phases</li>
2760<li>Type 1073, Compact GPS pseudo-ranges and carrier phases</li>
2761<li>Type 1074, Full GPS pseudo-ranges and carrier phases plus signal strength</li>
2762<li>Type 1075, Full GPS pseudo-ranges, carrier phases, Doppler and signal strength</li>
2763<li>Type 1076, Full GPS pseudo-ranges and carrier phases plus signal strength (high resolution)</li>
2764<li>Type 1077, Full GPS pseudo-ranges, carrier phases, Doppler and signal strength (high resolution)<br><br></li>
2765<li>Type 1081, Compact GLONASS pseudo-ranges</li>
2766<li>Type 1082, Compact GLONASS carrier phases</li>
2767<li>Type 1083, Compact GLONASS pseudo-ranges and carrier phases</li>
2768<li>Type 1084, Full GLONASS pseudo-ranges and carrier phases plus signal strength</li>
2769<li>Type 1085, Full GLONASS pseudo-ranges, carrier phases, Doppler and signal strength</li>
2770<li>Type 1086, Full GLONASS pseudo-ranges and carrier phases plus signal strength (high resolution)</li>
2771<li>Type 1087, Full GLONASS pseudo-ranges, carrier phases, Doppler and signal strength (high resolution)<br><br></li>
2772<li>Type 1091, Compact Galileo pseudo-ranges</li>
2773<li>Type 1092, Compact Galileo carrier phases</li>
2774<li>Type 1093, Compact Galileo pseudo-ranges and carrier phases</li>
2775<li>Type 1094, Full Galileo pseudo-ranges and carrier phases plus signal strength</li>
2776<li>Type 1095, Full Galileo pseudo-ranges, carrier phases, Doppler and signal strength</li>
2777<li>Type 1096, Full Galileo pseudo-ranges and carrier phases plus signal strength (high resolution)</li>
2778<li>Type 1097, Full Galileo pseudo-ranges, carrier phases, Doppler and signal strength (high resolution)<br><br></li>
2779<li>Type 4021, Compact SBAS pseudo-ranges</li>
2780<li>Type 4022, Compact SBAS carrier phases</li>
2781<li>Type 4023, Compact SBAS pseudo-ranges and carrier phases</li>
2782<li>Type 4024, Full SBAS pseudo-ranges and carrier phases plus signal strength</li>
2783<li>Type 4025, Full SBAS pseudo-ranges, carrier phases, Doppler and signal strength</li>
2784<li>Type 4026, Full SBAS pseudo-ranges and carrier phases plus signal strength (high resolution)</li>
2785<li>Type 4027, Full SBAS pseudo-ranges, carrier phases, Doppler and signal strength (high resolution)<br><br></li>
2786<li>Type 4031, Compact QZSS pseudo-ranges</li>
2787<li>Type 4032, Compact QZSS carrier phases</li>
2788<li>Type 4033, Compact QZSS pseudo-ranges and carrier phases</li>
2789<li>Type 4034, Full QZSS pseudo-ranges and carrier phases plus signal strength</li>
2790<li>Type 4035, Full QZSS pseudo-ranges, carrier phases, Doppler and signal strength</li>
2791<li>Type 4036, Full QZSS pseudo-ranges and carrier phases plus signal strength (high resolution)</li>
2792<li>Type 4037, Full QZSS pseudo-ranges, carrier phases, Doppler and signal strength (high resolution)</li>
2793</ul>
2794</p>
2795
2796<p><a name="config"><h4>5.3. Configuration Examples</h4></p>
2797
2798<p>BNC comes with a number of configuration examples which can be used on all operating systems. There are two ways to start BNC using one of these files:
2799<ul>
2800<li> On graphical systems you may use the computer mouse to 'drag' a configuration file icon and 'drop' it on top of BNC's program icon.
2801</li>
2802<li> On non-graphical systems you may start BNC using a command line with the following option for a configuration file (example for Windows systems):<br>bnc.exe --conf &lt;configFileName&gt;
2803</li>
2804</ul>
2805Presented example configuration files contain a user ID 'user' and a password 'pass' for accessing streams from various Ntrip Broadcasters. Replace these account details by a the personal user ID and password you receive following an online registration through <u>http://register.rtcm-ntrip.org</u>.
2806</p>
2807<p>
2808Note that the account for an Ntrip Broadcaster is usually limited to pulling a certain maximum number of streams at the same time. As running some of the example configurations requires pulling several streams, it is suggested to make sure that you don't exceed your account's limits.
2809</p>
2810<p>
2811Make also sure that directories which are part of the example configurations exist on your system or adjust the affected configuration options according to your needs.
2812</p>
2813<p>
2814Some BNC options require antenna phase center variations as made available from IGS through so-called ANTEX files at <u>ftp://igs.org/pub/station/general</u>. An example ANTEX file is also part of the BNC package for convenience.
2815</p>
2816<p>
2817The example configurations assume that no proxy protects your BNC host. Should a proxy be operated in front of BNC then you need to introduce its IP and port in the 'Network' tab.
2818</p>
2819
2820<ol type=b>
2821<li>File 'RinexObs.bnc'<br>
2822The purpose of this configuration is to convert RTCM streams to RINEX Observation files. The configuration pulls streams from several Ntrip Broadcasters using different Ntrip versions and generate 15min 1Hz RINEX Version 3 Observation files. See <u>http://igs.bkg.bund.de/ntrip/observations</u> for observation stream resources.
2823</li>
2824<br>
2825<li>File 'RinexEph.bnc'<br>
2826The purpose of this configuration is to convert RTCM streams to RINEX Navigation files. The configuration pulls an RTCM Version 3 stream carrying Broadcast Ephemeris coming from the real-time EUREF and IGS network. It saves hourly RINEX Version 3 Navigation files. See <u>http://igs.bkg.bund.de/ntrip/ephemeris</u> for further real-time Broadcast Ephemeris resources.
2827</li>
2828<br>
2829<li>File 'SSR.bnc'<br>
2830The purpose of this configuration is to save Broadcast Corrections from RTCM SSR messages in a plain ASCII format as hourly files. See <u>http://igs.bkg.bund.de/ntrip/orbits</u> for further real-time IGS or EUREF orbit/clock products.
2831</li>
2832<br>
2833<li>File 'RinexConcat.bnc'<br>
2834The purpose of this configuration is to concatenate RINEX Version 3 files to produce a concatenated file and edit the marker name in the file header. The sampling interval is set to 30 seconds. See section 'RINEX Editing & QC' in the documentation for examples on how to call BNC from command line in 'no window' mode for RINEX file editing, concatenation and quality checks.
2835</li>
2836<br>
2837<li>File 'RTK.bnc'<br>
2838The purpose of this configuration is to feed a serial connected receiver with observations from a reference station for conventional RTK. The stream is scanned for RTCM messages. Message type numbers and latencies of incoming observation are reported in BNC's logfile.
2839</li>
2840<br>
2841<li>File 'FeedEngine.bnc'<br>
2842The purpose of this configuration is to feed a real-time GNSS engine with observations from a number of remote reference stations. The configuration pulls streams provided in various formats from different Ntrip Broadcasters. Incoming observations are decoded, synchronized and output through a local IP port and saved into a file. Failure and recovery thresholds are specified to inform about outages.
2843</li>
2844<br>
2845<li>File 'PPP.bnc'<br>
2846The purpose of this configuration is Precise Point Positioning from observations of a rover receiver. The configuration reads RTCM Version 3 observations, a stream of Broadcast Corrections and a Broadcast Ephemeris stream. Positions are saved in the logfile.
2847</li>
2848<br>
2849<li>File 'QuickStartPPP.bnc'<br>
2850The purpose of this configuration is Precise Point Positioning in Quick-Start mode from observations of a static receiver with precisely known position. The configuration reads RTCM Version 3 observations, Broadcast Corrections and a Broadcast Ephemeris stream. Positions are saved in NMEA format on disc. Positions are also output through IP port for real-time visualization with tools like RTKPLOT.
2851</li>
2852<br>
2853<li>File 'PPPPostProc.bnc'<br>
2854The purpose of this configuration is Precise Point Positioning in Post Processing mode. BNC reads a RINEX Observation and a RINEX Version 3 Navigation files and a Broadcast Corrections files. PPP processing options are set to support the Quick-Start mode. The output is saved in a specific Post Processing logfile and contains the coordinates derived over time following the implemented PPP filter algorithm.
2855</li>
2856<br>
2857<li>File 'SPPQuickStartGal.bnc'<br>
2858The purpose of this configuration is Single Point Positioning in Quick-Start mode from observations of a static receiver with precisely known position. The configuration uses GPS, GLONASS and Galileo observations and a Broadcast Ephemeris stream.
2859</li>
2860<br>
2861<li>File 'Sp3.bnc'<br>
2862The purpose of this configuration is to produce SP3 files from a Broadcast Ephemeris stream and a Broadcast Corrections stream. Note that this requires an ANTEX file because SP3 file contents should be referred to CoM.
2863</li>
2864<br>
2865<li>File 'Sp3ETRF2000PPP.bnc'<br>
2866The purpose of this configuration is to produce SP3 files from a Broadcast Ephemeris stream and a stream carrying ETRF2000 Broadcast Corrections. The Broadcast Corrections stream is formally introduced in BNC's 'Combine Corrections' table. This leads to an SP3 file containing orbits referred also to ETRF2000. Pulling in addition observations from a reference station at precisely known ETRF2000 position allows to compare an 'INTERNAL' PPP solution with ETRF2000 reference coordinates.
2867</li>
2868<br>
2869<li>File 'Upload.bnc'<br>
2870The purpose of this configuration is to upload orbits and clocks from a real-time GNSS engine to an Ntrip Broadcaster. For that the configuration reads precise orbits and clocks in RTNET format. It also reads a stream carrying Broadcast Ephemeris. BNC converts the orbits and clocks into Broadcast Corrections and encodes them in RTCM Version 3 SSR messages to uploads them to an Ntrip Broadcaster. The Broadcast Corrections stream is referred to satellite Antenna Phase Center (APC) and IGS08. Orbits are saved on disk in SP3 format and clocks in Clock RINEX format.
2871</li>
2872<br>
2873<li>File 'UploadPPP.bnc'<br>
2874This configuration equals the 'Upload.bnc' configuration. However, the Broadcast Corrections are in addition used for an 'INTERNAL' PPP solution based on observations from a static reference station with known precise coordinates. This allows a continuous quality check of the Broadcast Corrections through observing coordinate displacements.
2875</li>
2876<br>
2877<li>File 'Combi.bnc'<br>
2878The purpose of this configuration is to pull several streams carrying Broadcast Corrections and a Broadcast Ephemeris stream from an Ntrip Broadcaster to produce a combined Broadcast Corrections stream. BNC encodes the combination product in RTCM Version 3 SSR messages and uploads that to an Ntrip Broadcaster. The Broadcast Corrections stream is not referred to satellite Center of Mass (CoM). It is referred to IGS08. Orbits are saved in SP3 format and clocks in Clock RINEX format.
2879</li>
2880<br>
2881<li>File 'CombiPPP.bnc'<br>
2882This configuration equals the 'Combi.bnc' configuration. However, the combined Broadcast Corrections are in addition used for an 'INTERNAL' PPP solutions based on observations from a static reference station with known precise coordinates. This allows a continuous quality check of the combination product through observing coordinate displacements.
2883</li>
2884<br>
2885<li>File 'UploadEph.bnc'<br>
2886The purpose of this configuration is to pull a number of streams from reference stations to get hold of contained Broadcast Ephemeris messages. These are encoded then in a RTCM Version 3 stream which only provides Broadcast Ephemeris with an update rate of 5 seconds.
2887</li>
2888</ol>
2889</p>
2890
2891<p>
2892The following table's left column is a list options as contained in BNC's configuration files (default: BNC.bnc).
2893</p>
2894<table>
2895<tr></tr>
2896<tr><td><b>Option</b></td><td><b>Affiliation</b></td></tr>
2897<tr><td>[General]</td><td>Settings: Group</td></tr>
2898<tr><td>startTab=</td><td>Internal: Top tab index</td></tr>
2899<tr><td>statusTab=</td><td>Internal: Bottom tab index</td></tr>
2900<tr><td>font=</td><td>Internal: Used font</td></tr>
2901<tr><td>casterUrlList=</td><td>Internal: Visited URLs</td></tr>
2902<tr><td>mountPoints=</td><td>Add Streams: broadcaster:port/mountpoint</td></tr>
2903<tr><td>ntripVersion=</td><td>Add Stream: NTRIP Version</td></tr>
2904
2905<tr><td>proxyHost=</td><td>Network: Proxy host</td></tr>
2906<tr><td>proxyPort=</td><td>Network: Proxy port</td></tr>
2907<tr><td>sslCaCertPath=</td><td>Network: Path to SSL certificates</td></tr>
2908<tr><td>ignoreSslErrors=0</td><td>Network: Ignore ssl authorization errors</td></tr>
2909
2910<tr><td>logFile=</td><td>General: Logfile (full path)</td></tr>
2911<tr><td>rnxAppend=</td><td>General: Append files</td></tr>
2912<tr><td>onTheFlyInterval=</td><td>General: Reread configuration</td></tr>
2913<tr><td>autoStart=</td><td>General: Auto start</td></tr>
2914<tr><td>rawOutFile=</td><td>General: Raw output file (full path)</td></tr>
2915
2916<tr><td>rnxPath=</td><td>RINEX Observations: Directory</td></tr>
2917<tr><td>rnxIntr=</td><td>RINEX Observations: Interval</td></tr>
2918<tr><td>rnxSample=</td><td>RINEX Observations: Sampling</td></tr>
2919<tr><td>rnxSkel=</td><td>RINEX Observations: Skeleton extension</td></tr>
2920<tr><td>rnxScript=</td><td>RINEX Observations: Uplod script</td></tr>
2921<tr><td>rnxV3=</td><td>RINEX Observation: Version 3</td></tr>
2922
2923<tr><td>ephPath=</td><td>RINEX Ephemeris: Directory</td></tr>
2924<tr><td>ephIntr=</td><td>RINEX Ephemeris: Interval</td></tr>
2925<tr><td>outEphPort=</td><td>RINEX Ephemeris: Port</td></tr>
2926<tr><td>ephV3=</td><td>RINEX Ephemeris: Version 3</td></tr>
2927
2928<tr><td>corrPath=</td><td>Broadcast Corrections: Directory, ASCII </td></tr>
2929<tr><td>corrIntr=</td><td>Broadcast Corrections: Interval</td></tr>
2930<tr><td>corrPort=</td><td>Broadcast Corrections: Port</td></tr>
2931<tr><td>corrTime=</td><td>Broadcast Corrections: Wait for full corr epoch</td></tr>
2932
2933<tr><td>outPort=</td><td>Feed Engine: Port</td></tr>
2934<tr><td>waitTime=</td><td>Feed Engine: Wait for full obs epoch</td></tr>
2935<tr><td>binSampl=</td><td>Feed Engine: Sampling</td></tr>
2936<tr><td>outFile=</td><td>Feed Engine: File (full path)</td></tr>
2937<tr><td>outUPort=</td><td>Feed Engine: Port (unsynchronized)</td></tr>
2938
2939<tr><td>serialMountPoint=</td><td>Serial Output: Mountpoint</td></tr>
2940<tr><td>serialPortName=</td><td>Serial Output: Port name</td></tr>
2941<tr><td>serialBaudRate=</td><td>Serial Output: Baud rate</td></tr>
2942<tr><td>serialFlowControl=</td><td>Serial Output: Flow control</td></tr>
2943<tr><td>serialDataBits=</td><td>Serial Output: Data bits</td></tr>
2944<tr><td>serialParity=</td><td>Serial Output: Parity</td></tr>
2945<tr><td>serialStopBits=</td><td>Serial Output: Stop bits</td></tr>
2946<tr><td>serialAutoNMEA=</td><td>Serial Output: NMEA</td></tr>
2947<tr><td>serialFileNMEA=</td><td>Serial Output: NMEA file name</td></tr>
2948<tr><td>serialHeightNMEA=</td><td>Serial Output: Height</td></tr>
2949
2950<tr><td>obsRate=</td><td>Outages: Observation rate</td></tr>
2951<tr><td>adviseFail=</td><td>Outages: Failure threshold</td></tr>
2952<tr><td>adviseReco=</td><td>Outages: Recovery threshold</td></tr>
2953<tr><td>adviseScript=</td><td>Outages: Script (full path)</td></tr>
2954
2955<tr><td>miscMount=</td><td>Miscellaneous: Mountpoint</td></tr>
2956<tr><td>perfIntr=</td><td>Miscellaneous: Log latency</td></tr>
2957<tr><td>scanRTCM=</td><td>Miscellaneous: Scan RTCM</td></tr>
2958
2959<tr><td>pppSPP=</td><td>PPP Client: PPP/SPP</td></tr>
2960<tr><td>pppMount=</td><td>PPP Client: Observations Mountpoint</td></tr>
2961<tr><td>pppCorrMount=</td><td>PPP Client: Corrections Mountpoint</td></tr>
2962<tr><td>pppRefCrdX=</td><td>PPP Client: X coordinate of plot origin</td></tr>
2963<tr><td>pppRefCrdY=</td><td>PPP Client: Y coordinate of plot origin</td></tr>
2964<tr><td>pppRefCrdZ=</td><td>PPP Client: Z coordinate of plot origin</td></tr>
2965<tr><td>pppRefdN=</td><td>PPP Client: North eccentricity</td></tr>
2966<tr><td>pppRefdE=</td><td>PPP Client: East eccentricity</td></tr>
2967<tr><td>pppRefdU=</td><td>PPP Client: Up eccentricity</td></tr>
2968<tr><td>nmeaFile=</td><td>PPP Client: NMEA outputfile</td></tr>
2969<tr><td>nmeaPort=</td><td>PPP Client: NMEA IP output port</td></tr>
2970<tr><td>pppPlotCoordinates=0</td><td>PPP Client: Plot NEU time series</td></tr>
2971<tr><td>postObsFile=</td><td>PPP Client: Observations file</td></tr>
2972<tr><td>postNavFile=</td><td>PPP Client: Navigation file</td></tr>
2973<tr><td>postCorrFile=</td><td>PPP Client: Corrections file</td></tr>
2974<tr><td>postOutFile=</td><td>PPP Client: Output file</td></tr>
2975<tr><td>pppAntenna=</td><td>PPP Client: Antenna name</td></tr>
2976<tr><td>pppAntex=</td><td>PPP Client: Path to ANTEX file</td></tr>
2977<tr><td>pppUsePhase=</td><td>PPP Client: Use phase data </td></tr>
2978<tr><td>pppEstTropo=</td><td>PPP Client: Estimate troposphere</td></tr>
2979<tr><td>pppGLONASS=</td><td>PPP Client: Use GLONASS</td></tr>
2980<tr><td>pppGalileo=</td><td>PPP Client: Use Galileo</td></tr>
2981<tr><td>pppSync=</td><td>PPP Client: Sync observations and corrections</td></tr>
2982<tr><td>pppAverage=</td><td>PPP Client: Lenght of time window for moving average</td></tr>
2983<tr><td>pppQuickStart=200</td><td>PPP Client: Quick-Start period</td></tr>
2984<tr><td>pppMaxSolGap=</td><td>PPP Client: Maximal Solution Gap</td></tr>
2985<tr><td>pppSigmaCode=</td><td>PPP Client: Sigma for Code observations</td></tr>
2986<tr><td>pppSigmaPhase=</td><td>PPP Client: Sigma for Phase observations</td></tr>
2987<tr><td>pppSigmaCrd0=</td><td>PPP Client: Sigma for initial XYZ coordinate</td></tr>
2988<tr><td>pppSigmaCrdP=</td><td>PPP Client: White noise for XYZ</td></tr>
2989<tr><td>pppSigmaTrp0=</td><td>PPP Client: Sigma for initial tropospheric delay</td></tr>
2990<tr><td>pppSigmaTrpP=</td><td>PPP Client: White noise for tropospheric delay</td></tr>
2991
2992<tr><td>reqcAction=</td><td>Reqc: Action</td></tr>
2993<tr><td>reqcObsFile=</td><td>Reqc: Observations file</td></tr>
2994<tr><td>reqcNavFile=</td><td>Reqc: Navigation file</td></tr>
2995<tr><td>reqcOutObsFile=</td><td>Reqc: Output observations file</td></tr>
2996<tr><td>reqcOutNavFile=</td><td>Reqc: Output navigation file</td></tr>
2997<tr><td>reqcPlotDir</td><td>Reqc: QC plots directory</td></tr>
2998<tr><td>reqcOutLogFile=</td><td>Reqc: Output logfile</td></tr>
2999<tr><td>reqcRnxVersion=</td><td>Reqc: RINEX version</td></tr>
3000<tr><td>reqcSampling=</td><td>Reqc: RINEX sampling</td></tr>
3001<tr><td>reqcStartDateTime=</td><td>Reqc: Start time</td></tr>
3002<tr><td>reqcEndDateTime=</td><td>Reqc: Stop time</td></tr>
3003<tr><td>reqcRunBy=</td><td>Reqc: Operators name</td></tr>
3004<tr><td>reqcComment=</td><td>Reqc: Additional comments</td></tr>
3005<tr><td>reqcOldMarkerName=</td><td>Reqc: Old marker</td></tr>
3006<tr><td>reqcNewMarkerName=</td><td>Reqc: New marker</td></tr>
3007<tr><td>reqcOldAntennaName=</td><td>Reqc: Old antenna</td></tr>
3008<tr><td>reqcNewAntennaName=</td><td>Reqc: New antenna</td></tr>
3009<tr><td>reqcOldReceiverName=</td><td>Reqc: Old receiver</td></tr>
3010<tr><td>reqcNewReceiverName=</td><td>Reqc: New receiver</td></tr>
3011
3012<tr><td>combineStreams=</td><td>Combination: List of correction streams</td></tr>
3013<tr><td>cmbMethod=Filter</td><td>Combination: Approach</td></tr>
3014<tr><td>cmbMaxres=</td><td>Combination: Clock outlier threshold</td></tr>
3015<tr><td>cmbSampl=</td><td>Combination: Orbit and clock sampling</td></tr>
3016
3017<tr><td>uploadIntr=</td><td>Upload Corrections: File interval</td></tr>
3018<tr><td>uploadMountpointsOut=</td><td>Upload Corrections: Upload streams</td></tr>
3019<tr><td>uploadSamplClkRnx=</td><td>Upload Corrections: Clock sampling</td></tr>
3020<tr><td>uploadSamplSp3=</td><td>Upload Corrections: Orbit sampling</td></tr>
3021<tr><td>uploadSamplRtcmEphCorr=</td><td>Upload Corrections: Orbit sampling</td></tr>
3022<tr><td>trafo_dx=</td><td>Upload Corrections: Translation X</td></tr>
3023<tr><td>trafo_dy=</td><td>Upload Corrections: Translation Y</td></tr>
3024<tr><td>trafo_dz=</td><td>Upload Corrections: Translation Z</td></tr>
3025<tr><td>trafo_dxr=</td><td>Upload Corrections: Translation change X</td></tr>
3026<tr><td>trafo_dyr=</td><td>Upload Corrections: Translation change Y</td></tr>
3027<tr><td>trafo_dzr=</td><td>Upload Corrections: Translation change Z</td></tr>
3028<tr><td>trafo_ox=</td><td>Upload Corrections: Rotation X</td></tr>
3029<tr><td>trafo_oy=</td><td>Upload Corrections: Rotation Y</td></tr>
3030<tr><td>trafo_oz=</td><td>Upload Corrections: Rotation Z</td></tr>
3031<tr><td>trafo_oxr=</td><td>Upload Corrections: Rotation change X</td></tr>
3032<tr><td>trafo_oyr=</td><td>Upload Corrections: Rotation change Y</td></tr>
3033<tr><td>trafo_ozr=</td><td>Upload Corrections: Rotation change Z</td></tr>
3034<tr><td>trafo_sc=</td><td>Upload Corrections: Scale</td></tr>
3035<tr><td>trafo_scr=</td><td>Upload Corrections: Scale change</td></tr>
3036<tr><td>trafo_t0=</td><td>Upload Corrections: Reference year</td></tr>
3037<tr><td>uploadEphHost=</td><td>Upload Ephemeris: Host</td></tr>
3038<tr><td>uploadEphPort=</td><td>Upload Ephemeris: Port</td></tr>
3039<tr><td>uploadEphMountpoint=</td><td>Upload Ephemeris: Moutpoint</td></tr>
3040<tr><td>uploadEphPassword=</td><td>Upload Ephemeris: Password</td></tr>
3041<tr><td>uploadEphSample=</td><td>Upload Ephemeris: Samplig</td></tr>
3042</table>
3043</p>
3044<p>
3045Note that the following configuration options saved on disk can be changed/edited on-the-fly while BNC is already processing data:
3046</p>
3047<p>
3048<ul>
3049<li>'mountPoints' to change the selection of streams to be processed, see section 'Streams',</li>
3050<li>'waitTime' to change the 'Wait for full obs epoch' option, see section 'Feed Engine', and</li>
3051<li>'binSampl' to change the 'Sampling' option, see section 'Feed Engine'.</li>
3052</ul>
3053</p>
3054<p>
3055</p>
3056
3057<p><a name="links"><h4>5.4 Futher Reading</h3></p>
3058
3059<table>
3060<tr></tr>
3061<tr><td><b>Links</b></td></tr>
3062<tr><td>NTRIP &nbsp;</td><td><u>http://igs.bkg.bund.de/ntrip/index</u></td></tr>
3063<tr><td>EUREF-IP NTRIP Broadcaster &nbsp;</td><td><u>http://www.euref-ip.net/home</u></td></tr>
3064<tr><td>IGS-IP NTRIP Broadcaster &nbsp;</td><td><u>http://www.igs-ip.net/home</u></td></tr>
3065<tr><td>IGS products NTRIP Broadcaster &nbsp;</td><td><u>http://products.igs-ip.net/home</u></td></tr>
3066<tr><td>IGS M-GEX NTRIP Broadcaster &nbsp;</td><td><u>http://mgex.igs-ip.net/home</u></td></tr>
3067<tr><td>Distribution of IGS-IP streams &nbsp;</td><td><u>http://www.igs.oma.be/real_time/</u></td></tr>
3068<tr><td>Completeness and latency of IGS-IP data &nbsp;</td><td><u>http://www.igs.oma.be/highrate/</u></td></tr>
3069<tr><td>NTRIP Broadcaster overview &nbsp;</td><td><u>http://www.rtcm-ntrip.org/home</u></td></tr>
3070<tr><td>NTRIP Open Source software code &nbsp;</td><td><u>http://software.rtcm-ntrip.org</u></td></tr>
3071<tr><td>EUREF-IP Project &nbsp;</td><td><u>http://www.epncb.oma.be/euref_IP</u></td></tr>
3072<tr><td>Real-time IGS Pilot Project &nbsp;</td><td><u>http://www.rtigs.net/pilot</u></td></tr>
3073<tr><td>Radio Technical Commission<br>for Maritime Services &nbsp;</td><td><u>http://www.rtcm.org</u>
3074</table>
3075
3076<br>
3077<table>
3078<tr><td><b>Publications</b></td></tr>
3079
3080<tr><td>Weber, G., D. Dettmering, H. Gebhard and R. Kalafus </td><td>Networked Transport of RTCM via Internet Protocol (Ntrip), IP-Streaming for Real-Time GNSS Applications, ION GNSS 2005.</td></tr>
3081
3082<tr><td>Weber, G, L. Mervart, Z. Lukes, C. Rocken and J. Dousa </td><td>Real-time Clock and Orbit Corrections for Improved Point Positioning via NTRIP, ION GNSS 2007.</td></tr>
3083
3084<tr><td>Mervart, L., Z. Lukes, C. Rocken and T. Iwabuchi </td><td>Precise Point Positioning With Ambiguity Resolution in Real-Time, ION GNSS 2008.</td></tr>
3085
3086<tr><td>Weber, G. and L. Mervart </td><td>The BKG Ntrip Client (BNC), Report on EUREF Symposium 2007 in London, Mitteilungen des Bundesamtes fuer Kartographie und Geodaesie, Band 42, Frankfurt, 2009.</td></tr>
3087
3088<tr><td>Weber, G. and L. Mervart </td><td>Real-time Combination of GNSS Orbit and Clock Correction Streams Using a Kalman Filter Approach, ION GNSS 2010.</td></tr>
3089
3090<tr><td>Huisman, L., P. Teunissen and C. Hu </td><td>GNSS Precise Point Positioning in Regional Reference Frames Using Real-time Broadcast Corrections, Journal of Applied Geodesy, Vol. 6, pp15-23, 2012.</td></tr>
3091
3092</table>
3093
3094
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