OXTS xNAV650, Руководство по оборудованию

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Specifications
Specifications for xNAV650 can be found in Tables 11, 12 and 13. These specifications are listed for
operation of the system under the following conditions:
▪
After a warm-up period of three minutes
’ continuous operation.
▪
Using combined post-processing the highest specification can be achieved effectively instantly for
the entire duration of the dataset but the warm-up manoeuvres should always be performed.
▪
Open-sky environment, free from cover by trees, bridges, buildings or other obstructions. The vehicle
must have remained in open sky for at least five minutes for full accuracy.
▪
The vehicle must exhibit some motion behaviour which should be achieved during the warmup.
Acceleration of the unit in different directions is required so the Kalman filter can estimate any errors
in the sensors. Without this estimation, some of the specifications degrade.
▪
The distance from the xNAV measurement point to the primary GNSS antenna must be known by
the system to a precision of five millimetres or better. The vibration of the system relative to the
vehicle cannot allow this to change by more than five millimetres. The system will estimate this value
itself in dynamic conditions.
▪
For dual antenna systems, the system must know the relative orientation of the two antennas to
0.05° or better (the system will estimate this value itself under dynamic conditions).
▪
For single antenna systems, the heading accuracy is only achieved under dynamic conditions. Under
benign conditions, such as motorway driving, the performance will degrade. The performance is
undefined when stationary for prolonged periods of time.
Table 11: xNAV650 performance specifications
Parameter Value
GNSS tracking GPS L1, L2
GLONASS L1, L2
BeiDou B1, B2
Galileo E1, E5b
Position accuracy
a
1.5 m CEP SPS
0.4 m DGPS
0.02 m RTK
Roll/pitch accuracy
0.05° 1

Heading accuracy
0.1° 1

b
Table 12: xNAV650 inertial sensor specifications
Accelerometers Value
Full range ±8 g
In-run bias stability 0.08 m g
Scale factor 0.08%
VRW 0.06 m/s/
√hr