125
NAV – DGPS (0x01 0x31)
It periodically polls DGPS correction data that are used in the navigation solution.
Header ID Data Length Data Checksum
0xB5 0x62 0x01 0x31 16+N*12 See below CK_A CK_B
Data
Offset bytes Format Descriptions Notes
0 U4 GPS time of week (ms)
4 I4 Age of newest correction data
(ms)
8 I2 DGPS reference station ID
10 I2 Health status for DGPS station
12 U1
umber of channels (correction
data is following)
13 U1 DGPS data type 00 – none
01 – PR+PRR correction
10 – PR+PRR+CP correction
11 – high accuracy PR+PRR+CP
correction
14 U2 Reserved
The following data will be repeated N times (number of channels).
16+N*12 U1 PRN number (SV ID)
17+N*12 U1 Flags Bit mask
0x01 ~ 0x08 – channel number
0x10 – DGPS used
0x20 ~ 0x80 – reserved
18+N*12 U2 Age of the latest correction data
(ms)
20+N*12 R4 Pseudo range correction (m)
24+N*12 R4 Pseudo range rate correction
(m/s)
