Patent ID: 6282231
Filing Date: 2001-08-28
Classification: G01S,H04B

Abstract:
A method of operating a spread spectrum radio signal receiver having at least first and second signal tracking channels to increase the interference discrimination between first and second received signals broadcast on the same carrier frequency band and modulated by first and second codes, respectively, the codes each having a known number of code phases, comprising the steps of:(a) receiving a first compound signal comprising the first and second received signals;(b) operating the first channel to track the first received signal and measure its amplitude, code phase, and received frequency;(c) selecting the received frequency and code phase of the second received signal;(d) operating the second channel at the selected code phase and received frequency of the second received signal to receive a second compound signal comprising the first and second signals;(e) computing the predicted code and frequency domain crosscorrelation of the first received signal with the second received signal;(f) multiplying the amplitude of the first received signal with the predicted crosscorrelation to compute the interference between the first and second received signals; and(g) subtracting the interference from the second compound signal to extract the second received signal including at least one of its received frequency, amplitude, and code phase.