This page is dedicated to the development of an RTCM3 Navigation data frames (NDF) message for the transport of raw GNSS messages.
| Data field | DF NUMBER | DATA TYPE | NO. OF BITS | NOTES
|
|---|
| Message Number | DF002 | uint12 | 12 | 4075 (proprietary number for this purpose)
|
| Reference Station ID | DF003 | uint12 | 12 | stream identification
|
| Reserved field | | uint2 | 2 | reserved bits, maybe used to separate different type 4075 message, always 0 for NDF
|
| Frame Count (FC) | | uint6 | 6 | Number of frame entries to follow
|
| Frame Entry | | | depends on FC and frame size | frame data according to following table
|
|
|
| TOTAL | | | 32 + Frames |
|
|---|
Frame Entry
| Data field | DF NUMBER | DATA TYPE | NO. OF BITS | NOTES
|
|---|
| Satellite system | | uint5 | 4 | 0 == GPS, 1 == GLONASS, 2 == Galileo, 3 = SBAS, 4 = QZSS, 5 = BDS
|
| Satellite number | | uint6 | 6 | Satellite ID, specific for the satellite system always 6 bits (see table below)
|
| Continuous Tracking | | bit(1) | 1 | Tracking this satellite frame data was continous (1 = continous, 0 not continues or unset)
|
| Epoch Time | | uint30 | 30 | Epoch time, specific for the satellite system always 30 bits (see table below)
|
| Signal Type | | uint5 | 5 | Signal type specification, index from MSM signal mask bit field (see DF395)
|
| Frame Data Size (N) | | uint12 | 12 | Number of bits to follow
|
| Frame Data | | | N | Bit data from satellite (see data section below)
|
|
|
| TOTAL | | | 48 + N |
|
|---|
Layout of a frame block always follows this structure, so unknown satellite systems or satellites can be skipped in messages with more than one frame.
Satellite ID (equal to MSM)
| Satellite system | DF NUMBER(s) | NOTES
|
|---|
| GPS | DF068 | 1 .. 32
|
| GLONASS | DF384 (with 6 bit) | 1 .. 24
|
| Galileo | DF252 | 1 .. 36
|
| SBAS | | 120 == 1, ...
|
| QZSS | DF429 (with 6 bit) | 192 == 1, ... 202 == 10
|
| BDS | | 1 .. 37
|
Epoch Time (accuracy in milli seconds, equal to MSM)
| Satellite system | DF NUMBER(s) | NOTES
|
|---|
| GPS | DF004 | in milliseconds (0..604799.99 ms)
|
| GLONASS | DF416 (3 bit) + DF034 (27 bit) | Like for MSM, Day of week (0 == Sunday, 6 == Saturday, 7 == unknown) + time of day in ms (0..86400.999 ms)
|
| Galileo | DF248 | equals GPS
|
| SBAS | | equals GPS
|
| QZSS | DF428 | equals GPS
|
| BDS | DF427 | similar to GPS, but with a 14 leap second difference
|
Frame Data
