u-blox ANTARIS 4 User Manual


GPS Positioning is weightedmoreheavily as longas the GPS parameter (e.g. DOP, number of satellites, signal
ations, wherethe GPS signalsare poor, reflected from
withahigherweighting.
quality) indicates good andreliableperformance. In situ
buildings(multipath)orjammed,theDRsolutionisused
Poor GPSNo GPS Good GPS
GPS DRGPS DRGPS DR
Extrapolation
Blending Calibration
EKF
EKF EKF
Position,Velocity,Time
Position,Velocity,Time
y,Timefrom
eclock
Position,Velocit
real-tim
Altitudeheldconstant

Fig re 30: Dead Reckoning Blending u
(sensor based) positions are reported. The position is calculated
based on the signals of the turn rate sensor and speed sensor, with reference to the last
 reception, the

S and sensor based
•
situation, the
GPS position values are used to
calibrate the DR sensors or to perform sensor integrity
checks(toestablishifthesensorsarewellcalibrated).

• No GPS: During GPS loss, only DR-
knownGPSsolution.
• Poor GPS: In urban canyons with fast changing sky visibility or during degraded GPS
ANTARIS
®
4 DR Technology performs a calculation by blending the GP
positioning.
Good GPS: With good GPS performance and optimal sky view, the GPS position has a higher weight
than the DR/sensor based position on the overall navigation solution. In this

GPSModules-SystemIntegrationManual(SIM)(incl.ReferenceDesign) GPSFundamentals
GPS.G4-MS4-05007-A1
  Page 34

u-blox ANTARIS 4 Specifications

General

Brand	u-blox
Model	ANTARIS 4
Category	GPS
Language	English