ashtech GG Surveyor, Справочное руководство

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Command/Response Formats 139
Com
m
and
s
Range residuals are recomputed after the GGA position is computed. Therefore the mode m is
always 1. There will be a range residual sxx.x for each satellite used in position computation, where
range residuals for GPS satellites are included in the GPGRS message, and range residuals for
GLONASS satellites are included in the GLGRS message.
Table 6.49 outlines the GRS message structure.
Example:
Query: $PASHQ,GRS,A or
Set: $PASHS,NME,GSN,A,ON
Response: $GPGRS,180257.50,1,+00.3,-00.4,+00.2,+00.5,+00.7,-00.8*64
$GLGRS,180257.50,1,-00.2,+00.4,+00.3,-00.6,+00.5*38
Table 6.50 outlines a typical GPGRS response message. Table 6.51 outlines a typical
GLGRS response message.
Table 6.49: GRS Structure
Field Description
m1 Current UTC time, (hhmmss.ss), of GGA position fix in hours, minutes, and seconds
hh = Hours (00 to 23)
mm = Minutes (00 to 59)
ss.ss = Seconds (00.00 to 59.99)
d1 Mode, used to compute range residuals
0 - Residuals were used to calculate the position given in the matching GGA line
1 - residuals were recomputed after the GGA position was computed
f1 Range residuals (sign s = + or -, and magnitude xx.x) for each satellite used in
position computation.
Table 6.50: Typical GPGRS Response Message
Field Significance
$GPGRS Header
180257.50 Time of position fix
1 Mode
+00.3 Range residual for first GPS satellite
-00.4 Range residual for second GPS satellite
+00.2 Range residual for third GPS satellite
+00.5 Range residual for fourth GPS satellite