GPGST
Estimated error in position solution
Platform: 
OEM719, OEM729, OEM7500, OEM7600, OEM7700, OEM7720, PwrPak7, CPT7, CPT7700, SMART7, SMART2 
This log contains pseudorange measurement noise statistics are translated in the position domain in order to give statistical measures of the quality of the position solution.
This log reflects the accuracy of the solution type used in the BESTPOS log and GPGGA log, except for the RMS field. The RMS field, since it specifically relates to pseudorange inputs, does not represent carrierphase based positions. Instead, it reflects the accuracy of the pseudorange position which is given in the PSRPOS log.
The GPGST log outputs these messages without waiting for a valid almanac. Instead, it uses a UTC time, calculated with default parameters. In this case, the UTC time status (see the TIME log) is set to WARNING since it may not be one hundred percent accurate. When a valid almanac is available, the receiver uses the real parameters. Then the UTC time status is set to VALID.
If the NMEATALKER command is set to AUTO, the talker (the first 2 characters after the $ sign in the log header) is set to GP (GPS satellites only), GL (GLONASS satellites only) or GN (satellites from multiple systems) or GA (Galileo satellites only).
Message ID: 222
Log Type: Synch
Recommended Input:
log gpgst ontime 1
Example 1 (GPS only):
$GPGST,141451.00,1.18,0.00,0.00,0.0000,0.00,0.00,0.00*6B
Example 2 (Combined GPS and GLONASS):
$GNGST,143333.00,7.38,1.49,1.30,68.1409,1.47,1.33,2.07*4A


Field 
Structure 
Description 
Symbol 
Example 
1 
$GPGST 
Log header. See Messages for more information. 

$GPGST 
2 
utc 
UTC time status of position 
hhmmss.ss 
173653.00 
3 
rms 
RMS value of the standard deviation of the range inputs to the navigation process. Range inputs include pseudoranges and DGPS corrections 
x.x 
2.73 
4 
smjr std 
Standard deviation of semimajor axis of error ellipse (m) 
x.x 
2.55 
5 
smnr std 
Standard deviation of semiminor axis of error ellipse (m) 
x.x 
1.88 
6 
orient 
Orientation of semimajor axis of error ellipse (degrees from true north) 
x.x 
15.2525 
7 
lat std 
Standard deviation of latitude error (m) 
x.x 
2.51 
8 
lon std 
Standard deviation of longitude error (m) 
x.x 
1.94 
9 
alt std 
Standard deviation of altitude error (m) 
x.x 
4.30 
10 
*xx 
Check sum 
*hh 
*6E 
11 
[CR][LF] 
Sentence terminator 

[CR][LF] 