Changeset 1248 in ntrip


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Timestamp:
Dec 1, 2008, 12:10:39 AM (15 years ago)
Author:
weber
Message:

* empty log message *

File:
1 edited

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  • trunk/BNS/bnshelp.html

    r1221 r1248  
    296296<p><a name="ephcsys"><h4>4.7.3 System - mandatory if 'Host' is set</h4></p>
    297297<p>
    298 BNS refers its final clock and orbit corrections to a specific reference system. Available options are
    299 <p>
    300 <ul>
    301 <li>IGS05 which stands for the GNSS-based IGS realization of the International Terrestrial Reference Frame (ITRF2005), and</li>
    302 <li>ETRS89 which stands for the European Terrestrial Reference System 1989 adopted by EUREF.</li>
    303 </ul>
    304 </p>
    305 
    306 <p>
    307 <u>IGS05:</u>
    308 As the clocks and orbits coming from real-time GNSS engine are expected to be in the IGS05 system, no transformation is carried out if this option is selected.
    309 </p>
    310 <p>
    311 <u>ETRS89:</u>
    312 From the complete transformation chain 'IGS05->ITRF2005->ITRF2000->ETRS89' only the transformation 'ITRF2000->ETRS89' has been implemented. The formulas for that are taken from 'Boucher and Altamimi 2007: Specifications for reference frame fixing in the analysis of EUREF GPS campaign', see <u>http://etrs89.ensg.ign.fr/memo2007.pdf</u>. The following 6 Helmert transformation parameters were introduced:
     298BNS refers its clock and orbit corrections to a specific reference system. Available options are
     299<p>
     300<ul>
     301<li>IGS05 which stands for the GNSS-based IGS realization of the International Terrestrial Reference Frame 2005 (ITRF2005), and</li>
     302<li>ETRF2000 which stands for the European Terestrial Reference Frame 2000 adopted by EUREF.</li>
     303</ul>
     304</p>
     305
     306<p>
     307<u>IGS05:</u> As the clocks and orbits coming from real-time GNSS engine are expected to be in the IGS05 system, no transformation is carried out if this option is selected.
     308</p>
     309<p>
     310<u>ETRF2000:</u> The formulars for the transformation 'ITRF2005->ETRF2000' are taken from 'Claude Boucher and Zuheir Altamimi 2008: Specifications for reference frame fixing in the analysis of EUREF GPS campaign'. The following 14 Helmert transformation parameters were introduced:
    313311</p>
    314312<p>
    315313<pre>
    316 Translation in X:  0.054 m
    317 Translation in Y:  0.051 m
    318 Translation in Z: -0.048 m
     314Translation in X at epoch To:  0.0541 m
     315Translation in Y at epoch To:  0.0502 m
     316Translation in Z at epoch To: -0.0538 m
     317Translation rate in X: -0.0002 m/y
     318Translation rate in Y:  0.0001 m/y
     319Translation rate in Z: -0.0018 m/y
     320Rotation in X at epoch To:  0.891 mas
     321Rotation in Y at epoch To:  5.390 mas
     322Rotation in Z at epoch To: -8.712 mas
    319323Rotation rate in X:  0.081 mas/y
    320324Rotation rate in Y:  0.490 mas/y
    321325Rotation rate in Z: -0.792 mas/y
    322 T0: 1989
     326Scale at epoch To : 0.00000000040
     327Scale rate: 0.00000000008 /y
     328To: 2000.0
    323329</pre>
    324330</p>
    325331<p>
    326 Note that the neglect of transformations 'IGS05->ITRF2005->ITRF2000' in BNS may cause discrepancies up to a maximum of 2 centimenters.
     332Contact [igs-ip@bkg.bund.de] if you would like to see further transformations implemented in BNS.
    327333<p>
    328334
     
    425431</li>
    426432<li>
    427 Currently BNS can only generate premature RTCM Version 3.x message Type 4056 and 4057 for combined GPS and GLONASS orbit and clock corrections. Note that the length of data fields in these messages is not yet standardized. What's implemented in BNS is just a temporary solution.
     433Currently BNS can only generate premature RTCM Version 3.x message Type 4056 and 4057 for combined GPS and GLONASS orbit and clock corrections, see RTCM document 026-2008-SC104-429 'Version 1 Proposed SSR Messages prepared by Geo++'. Note that the length of data fields in these messages is not yet standardized. What's implemented in BNS is just a temporary solution.
    428434</li>
    429435<li>
     
    460466<table>
    461467<tr></tr>
    462 <tr><td>Nov 2008 &nbsp;</td><td>Version 1.0 &nbsp;</td><td>[Add] Source code and binaries published.</td></tr>
     468<tr><td>Dec 2008 &nbsp;</td><td>Version 1.0 &nbsp;</td><td>[Add] Source code and binaries published.</td></tr>
    463469</table>
    464470</p>
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