NavCom Sapphire Rev.J - Manual (Page 314)

Sapphire Technical Reference Manual Rev. J
314
2.63 NMEAGRS (ASCII)
SF-3050 Sapphire SF-3040
Supported Output Rate: OFF ONCE OnChange OnTime
OnChange = when slow nav is completed (1Hz)
OnTime = minimum 1Hz
This output stream reports Receiver Autonomous Integrity Monitoring (RAIM) data, reporting
Range Residuals in compliance with NMEA 0183 Standards version 3.0. NMEA 0183 v4.1 are
given by the addition of fields F9 and F10.
Table 150: GRS Message Output Format
Output Format: $GPGRS,UTC,Mode,Res…,Res,*checksum
Field# Field Name Description
F1 UTC UTC time of the associated GGA or GNS fix (hhmmss.ss)
F2 Mode How the residuals were calculated (see note 1)
F3 Res Up to 12 range residuals (+/999 meters) (see note 2)
F9 System ID 1 for GPS, 2 for GLONASS (NMEA v4.1 only)
F10
Signal ID 1 for Single Mode, and 0 for Dual Mode (see note 3)
(NMEA v4.1 only)
F11 *CRC Checksum
Example: $GPGRS,162404.00,0,-0.2,-0.9,-0.3,0.9,-0.5,0.2,0.4,0.1,0.6,0.7,0.5*4F

1 Mode 0 means the residuals were used to calculate the position given in the
matching GGA or GNS sentence. Mode 1 means the residuals were recomputed
after the GGA or GNS position was computed.
2
The order of the range residuals must match the order of the satellite ID numbers
given in the GSA command.
3 The Signal ID is designed to show the Signals that are being tracked, but since the
GRS shows the risiduals for multiple sats that are being used in the navigation
solution, the Signal ID will be used to inform the user of the signals that are being
used for the nav solution. If the nav solution is based on a Single Frequency, then
this Signal ID will be 1 for GPS and 1 for GLONASS, corresponding to the L1C/A
and G1C/A signal. If the nav solution is based on a Dual Frequency, then the
Signal ID will be 0 for both GPS and GLONASS, since there are multiple signals
contributing to the solution. The All signals ID means that the navigation solutionis
using L1C/A and L2 P(Y) signals. Refer to the graphic on the next page.