User's Manual

B GSOF Messages
96 SPSx80 Smart GPS Antenna User Guide
• Covariance east-north
• Error Ellipse Semi-major axis, in meters
• Error Ellipse Semi-minor axis, in meters
• Orientation of Semi-major axis in degrees from True North
• Unit variance
• Number of epochs
SV Brief
This message provides brief satellite information. It contains the following data:
• Number of satellites tracked
• The PRN number of each satellite
• Flags indicating satellite status
Table B.8 Sigma (Type 12 record)
Field Item Type Value Meaning
0 Output record type Char 0Ch Position sigma information output record
1 Record length Char 26h Bytes in record
2–5 Position RMS Float Root means square of position error calculated
for overdetermined positions
6–9 Sigma east Float Meters
10–13 Sigma north Float Meters
14–17 Covar. east-north Float number Covariance east-north (dimensionless)
18–21 Sigma up Float Meters
22–25 Semi-major axis Float Meters Semi-major axis of error ellipse
26–29 Semi-minor axis Float Meters Semi-minor axis of error ellipse
30–33 Orientation Float degrees Orientation of semi-minor axis, clockwise from
True North
34–37 Unit variance Float Valid only for over-determined solutions. Unit
variance should approach 1.0 value. A value of
less than 1.0 indicates that apriori variances are
too pessimistic.
30–39 Number of epochs short count Number of measurement epochs used to
compute the position. Could be greater than 1
for positions subjected to static constraint.
Always 1 for kinematic.
Table B.9 SV brief (Type 13 record)
Field Item Type Value Meaning
0 Output record type Char 0Dh Brief satellite information output record
1 Record length Char Bytes in record
2 Number of SVs Char 00h-18h Number of satellites included in record
1