About Clock And Time Conversion Parameters And Errors - R&S SMW-K44 User Manual

Satellite Navigation
Figure 12-2: Satellite orbit (GLONASS): Understanding the displayed information
1 = Reference epoch, t
2 = Coordinates in PZ-90
3 = Velocity component
4 = Moon and sun acceleration

12.1.3 About Clock and Time Conversion Parameters and Errors

Clock and time conversion errors
Satellites and receivers can suffer from timing errors. Although satellites are equipped
with very precise clocks, there is always a clock offset due to:
●
Clock drift between the different SVs.
●
Misalignment in the time bases of the different GNSS systems.
The clock in the receiver is usually less precise and is hence a prone of an additional
drift.
To counteract the drifts in the satellites and GNSS systems time, the navigation mes-
sage contains satellite clock offset and time conversion parameters, see
clock parameters"
The receiver clock synchronization errors are estimated and compensated during the
positioning measurements, because the receiver clock offset is a constant value pres-
ent in the measurements of all satellites.
User Manual 1178.6379.02 ─ 01
; orbit parameters are given at t
b
on page 105.
Perturbations and Errors Simulation
About the Errors Sources
b
"Satellite
104