Patent ID: 6560440
Filing Date: 2003-05-06
Classification: H04B,H04L

Abstract:
In a satellite communications system involving a satellite vehicle SV1 and a second satellite vehicle SV2 moving relative to one another, a method for compensating at least one of a transmission frequency associated with SV1 and a received frequency associated with SV2, the method comprising the steps of:predicting a motion of satellite vehicle SV1 and generating a first output signal representative of the predicted motion of satellite vehicle SV1; predicting a motion of satellite vehicle SV2 and generating a second output signal representative of the predicted motion of satellite vehicle SV2; supplying said first output signal and said second output signal to a processor and computing in said processor at least one of a compensated transmission frequency and a compensated receiving frequency based on said first output signal and said second output signal; determining an actual motion of SV1 and generating a third output signal representative of the actual motion of SV1; determining an actual motion of SV2 and generating a fourth output signal representative of the actual motion of SV2; supplying said first output signal and said third output signal to a first summing junction and generating a first feedback signal representative of the difference between said first output signal and said third output signal; supplying said second output signal and said fourth output signal to a second summing junction and generating a second feedback signal representative of the difference between said second output signal and said fourth output signal; using said first feedback signal to improve the accuracy of said first output signal; and using said second feedback signal to improve the accuracy of said second output signal.