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your position is our focus
4.6.9 Position Quality
6.9.1 NMEA Valid Flag ator)
position fix is declared as v of the conditions below are met:
Position fix with at least ). In order to ensure a good accu e ANTARIS
®
4 GPS
Technology does not sup
The ‘3D Position Accurac needs to be below the ‘Position Accuracy Mask
The PDOP value needs to ‘PDOP Accuracy Mask’.
te The ‘Position Accuracy Mask’ are configurable. This customizing the
behavior of the va n requirements (see Section 4.6.8 )
ds (valid flags) for the different NMEA message for NMEA standard 0183
2.3:
Indicators
4. (Position Fix Indic
A alid if all
•
3 satellites (2D or 3D fix racy, th
port 1D fixes.
•
y Estimate’ ’
•
be below the
No Mask’ and th
lid flag to applicatio
e ‘PDOP allows
Table 32 lists of the status fiel
Version
NMEA
Message
Field
No Position Fix
(after power-up,
after losing
Satellite lock)
Valid Position Fix
but User
Limits exceeded
Dead
Reckoning
(linear extra-
polation)
EKF
11
2D Position
Fix
3D
Position Fix
Combined
GPS/EKF
Position Fix
0 0 6 6 1/2 1/2 1/2
GGA Status
0=Fix not available/invalid, 1=GPS SPS Mode, Fix valid
12
, 2=Differential GPS, SPS Mode, Fix Valid,
6=Estimated/Dead Reckoning
V V V A
13
A A A
Status
A=Data VALID, V=Data Invalid (Navigation Receiver Warning)
N N E E A/D A/D A/D
GLL
Mode Indicator
N=No Fix, A=Autonomous GNSS Fix, D=Differential GNSS Fix, E=Estimated/Dead Reckoning Fix
1 1 2 2 2 3 3
GSA Nav Mode
1=Fix Not available, 2=2D Fix, 3=3D Fix
V V V A A A A
Status
A=Data VALID, V=Data Invalid (Navigation Receiver Warning)
N N E E A/D A/D A/D
RMC
Mode Indicator
N=No Fix, A=Autonomous GNSS Fix, D=Differential GNSS Fix, E=Estimated/Dead Reckoning Fix
N N E E A/D A/D A/D
VTG ode Indicator M
N=No Fix, A=Autonomous GNSS Fix, D=Differential GNSS Fix, E=Estimated/Dead Reckoning Fix
Table 32: NMEA Valid Flag (0183 Version 2.3)
11
TIM-LR / DR enabled receivers only
12
For DR enabled receiver a valid fix is always a combination of a GPS fix with a DR position based on the attached DR sensor (turn rate
sensor, odometer)-
13
For DR enabled receivers the EKF only fix is considered as valid as long as it’s within the defined accuracy range.
GPS Modules - System Integration Manual (SIM) (incl. Reference Design) Receiver Description
GPS.G4-MS4-05007-A1 Page 102