14
Oxford Technical Solutions
Specification
Specifications for RT products can be found in Table 3 and Table 4. These specifications are
listed for operation of the system under the following conditions:
•
After a warm-up period of 15 minutes’ continuous operation.
•
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. 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 RT 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.
Optionally, extended measurement ranges covering 30
g
acceleration and 300°/s
angular rate may be requested. The specification using the extended measurement
range sensors can be marginally worse than those listed here.