Application of Autoregressive Methods to Adaptive Excision of Interfering Tones from Direct Sequence Spread Spectrum Communications Systems

摘要

A Computer Simulation of a BPSK Direct Sequence Spread Spectrum System has been developed to investigate the effects of adaptively filtering stable tone interferers covering twenty per cent of the communication band. Preliminary results for the swept tone interfering signal are also presented and shows that the block filter is effective when the tones are stable, but degrades in performance as the tone sweeps quickly across the band. To combat the non-stationary signal environment, either shorter block lengths may be required or the use of recursive algorithms that are based on gradient or least square concepts may have to be examined. Keywords: Spread spectrum; Binary phase shift keyers; Spectrum estimation; Computer simulation; Autoregressive processes; Maximum entropy method; Least squares; Adaptive filtering; Signal excision; Weiner filtering; Linear prediction; Canada. (jd/rh)