Eigenvalue behavior in FH signal rejection in DS spread spectrum systems using complex adaptive filters

Abstract

Eigenvalue behavior of direct sequence (DS) QPSK spread spectrum (SS) receiver using adaptive filters in presence of frequency hopped (FH) interference is analyzed. The analysis is valid both for the adaptive prediction error filters and for transversal filters with two-sided taps. The improvement factor G depends on filter adaptation rate μ and on transient response of the filter. Thansient responses of the filters using eigenvalue behavior method are analyzed. Presented analysis and results show that slow FH jammer suppression in DS system can be obtained using complex adaptive filters. The adaptation rate dependance on different communication parameters and on discrete time is presented.