SkyTraq PX1175RDP - Page 18

18
GSA – GNSS DOP and Active Satellites
GNSS receiver operating mode, satellites used in the navigation solution reported by the GGA or GNS sentence and
DOP values.
Structure:
$GNGSA,A,x,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,x.x,x.x,x.x,x*hh<CR><LF>
1 2 3 3 3 3 3 3 3 3 3 3 3 3 4 5 6 7 8
Example:
$GNGSA,A,3,02,05,06,12,13,19,20,193,195,199,,,1.0,0.5,0.9,1*01<CR><LF>
$GNGSA,A,3,03,05,09,36,,,,,,,,,1.0,0.5,0.9,3*34<CR><LF>
$GNGSA,A,3,06,07,08,09,10,19,22,29,35,38,39,40,1.0,0.5,0.9,4*38<CR><LF>
$GNGSA,A,3,44,,,,,,,,,,,,1.0,0.5,0.9,4*39<CR><LF>
$GNGSA,A,3,02,03,,,,,,,,,,,1.1,0.5,1.0,6*33<CR><LF>
Field
Name
Example
Description
1
Mode
A
Mode
‘M’ = Manual, forced to operate in 2D or 3D mode
‘A’ = Automatic, allowed to automatically switch 2D/3D
2
Mode
3
Fix type
1 = Fix not available
2 = 2D
3 = 3D
3
Satellite used 1~12
02,05,06,12,13,1
9,20,193,195,19
9
01 ~ 32 are for GPS; 33 ~ 64 are for WAAS (PRN minus 87); 193
~ 197 are for QZSS; 65 ~ 88 are for GLONASS (GL PRN) ; 01 ~ 36
are for GALILEO (GA PRN); 01 ~ 37 are for BDS (BD PRN). GPS,
GLONASS, GALILEO and BDS satellites are differentiated by the
GNSS system ID in table 3. Maximally 12 satellites are included
in each GSA sentence.
4
PDOP
1.0
Position dilution of precision (0.0 to 99.9)
5
HDOP
0.5
Horizontal dilution of precision (0.0 to 99.9)
6
VDOP
0.9
Vertical dilution of precision (0.0 to 99.9)
7
GNSS System ID
1
GNSS system ID
*
1 = GPS
2 = GLONASS
3 = GALILEO
4 = BDS
5 = IRNSS
8
Checksum
01
*GNSS System ID identifies the GNSS system ID according to Table 3.