Users manual
Appendix A
Revision #:
A
Date:
07-14-15
Page
12
of
58
GSA
–
GNSS DOP and Active Satellites
△
4
Format:
$XXGSA , a , a , xx , xx , xx , … , xx , x.x , x.x , x.x , h *hh <CR> <LF>
1
2
3
4
5
6-13
14
15
16
17
18
#
1.
Description
Operational mode
Range
M or A
“M”: 2D/3D fixed mode
“A”: 2D/3D Auto-switching mode
2.
Mode
1 - 3
“1”: No fix
“2”: 2D fix
“3”: 3D fix
3-14. Satellite Numbers used for positioning
01 - 99
Note: A null field is output unless a satellite is available.
15.
PDOP
0.0 - 50.0
Note: A null field is output unless 3D-positioning is performed.
16.
HDOP
0.0 - 50.0
Note: A null field is output while positioning is interrupted.
17.
VDOP
0.0 - 50.0
Note: A null field is output unless 3D-positioning is performed.
18.
GNSS System ID
n/a
Example:
$GNGSA,A,3,09,15,26,05,24,21,08,02,29,28,18,10,0.8,0.5,0.5,1*33
$GNGSA,A,3,79,69,68,84,85,80,70,83,,,,,0.8,0.5,0.5,2*30
2D/3D Auto-switching mode, 3D fix
Satellite used: 09, 15, 26, 05, 24, 21, 08, 02, 29, 28, 10, 79, 69, 68, 84, 85, 80, 70, 83
PDOP: 0.8 HDOP: 0.5 VDOP: 1.5
Notes:
△
4
-
To adds extra fields to the GPGSA NMEA string to show more than 12 satellites used in the fix,
please input “$PERDAPI,EXTENDGSA,num*hh<CR><LF>”. num is Number of fields for satellites
used in the fix. Acceptable values are: 12-16. Default num is 12. By creating more fields for satellites
used in the fix, the PDOP/HDOP/VDOP values shift by num12 fields.
-
Satellite number means the follow.
Satellite number from 01 to 32 indicates GPS (01 to 32)
Satellite number from 33 to 51 indicates SBAS (120 to 138)
Satellite number from 65 to 92 indicates GLONASS (slot 01 to slot 28)
Satellite number from 93 to 99 indicates QZSS (193 to 199)
