User's Manual

SPSx50 Modular GPS Receiver User Guide 137
GSOF Messages B
• Heading, in radians, referenced to WGS-84 True North
PDOP
This message describes the PDOP information. It contains the following data:
• PDOP
• HDOP
• VDOP
• TDOP
SIGMA
This message describes the position sigma information. It contains the following data:
• Position RMS
• Sigma east, in meters
• Sigma north, in meters
• Sigma up, in meters
• Covariance east-north
• Error Ellipse Semi-major axis, in meters
• Error Ellipse Semi-minor axis, in meters
Table B.6 Velocity (Type 8 record)
Field Item Type Value Meaning
0 Output record type Char 08h Velocity data output record
1 Record length Char 0Dh Bytes in record
2 Velocity flags Char See
Table B.17
Velocity status flags
3-6 Speed Float Meters per
second
Horizontal speed
7-10 Heading Float Radians True north heading in the WGS-84 datum
11-14 Vertical velocity Float Meters per
second
Vertical velocity
Table B.7 PDOP (Type 9 record)
Field Item Type Value Meaning
0 Output record type Char 09h PDOP information output record
1 Record length Char 10h Bytes in record
2-5 PDOP Float Positional Dilution of Precision
6-9 HDOP Float Horizontal Dilution of Precision
10-13 VDOP Float Vertical Dilution of Precision
14-17 TDOP Float Time Dilution of Precision