Patent ID: 6219373
Filing Date: 2001-04-17
Classification: G01S,G06F,H04K

Abstract:
A method of filtering out interference from a spread-spectrum signal, comprising the steps of:applying a wavelet packet decomposition scheme to a spread-spectrum signal having a known noise floor wherein a first plurality of coefficient sets are generated, each of said first plurality of coefficient sets corresponding to a unique wavelet decomposition level;determining an entropy measurement for each said wavelet decomposition level using a corresponding one of said first plurality of coefficient sets;filtering out portions of said spread-spectrum signal occurring above said known noise floor for said wavelet decomposition level having the lowest said entropy measurement wherein a revised coefficient set is generated for said wavelet decomposition level having the lowest said entropy measurement, and wherein a second plurality of coefficient sets is formed such that said first plurality of coefficient sets differs from said second plurality of coefficient sets only by said revised coefficient set; andforming a new signal by applying a wavelet packet reconstruction scheme to said second plurality of coefficient sets.