OmniSTAR 5220HP, User Manual

Page: 65 / 83

OmniSTAR 5220HP User Manual
Issue 1.32 12/2010
65
GST – GPS Pseudorange Noise Statistics
The GST message is used to support Receiver Autonomous Integrity
Monitoring (RAIM).
$GPGST,hhmmss.ss,S.S,M.M,m.m,ddd.d,y.y,x.x,h.h,*XX
Field Number Description
1 UTC time of GGA fix
2 RMS value of the standard deviation of the range
inputs to the navigation process (range inputs
include pseudoranges and DGPS corrections)
3 Standard deviation of semi-major axis of error
ellipse, in meters
4 Standard deviation of semi-minor axis of error
ellipse, in meters
5 Orientation of semi-major axis of error ellipse, in
degrees from true north
6 Standard deviation of latitude error, in meters
7 Standard deviation of longitude error, in meters
8 Standard deviation of altitude error, in meters
Table 11: Description of the GST message.
NOTE:
Because the contents of this NMEA message do not change significantly
during a 1-second interval, the receiver outputs this message at a
maximum rate of 1 Hz.