ELECTRONIC ARTICLE SURVEILLANCE SYSTEM WITH COMB FILTERING BY POLYPHASE DECOMPOSITION AND NONLINEAR FILTERING OF SUBSEQUENCES

摘要

A signal (120) received (124) in an electronic article surveillance system (100) is subjected to a nonlinear comb filtering function to remove interference. The nonlinear comb filtering is provided (130) by performing a polyphase decomposition of an input digital signal (128), nonlinear filtering of the resulting subsequences, and then synthesizing the nonlinear-filtered subsequences (130). A median filter may be used as the subsequence filtering function. A linear comb filtering function may be provided (130) downstream from the nonlinear comb filter to provide additional attenuation of interference.