USING THRESHOLD AND NO-THRESHOLD METHODS OF DISCRETE WAVELET FILTERING OF RADIO LOCATION SIGNALS

Abstract

The paper examines the effectiveness of threshold and non-threshold wavelet noise filtering methods in processing radar signals. Three methods of wavelet analysis are analyzed: a method with a general threshold for limiting wavelet coefficients of detail; a method with a universal threshold for all wavelet decompositions; and a method without a threshold, based on zeroing the coefficients of detail at certain levels of the wavelet decomposition of the signal. The effectiveness of wavelet filtering is evaluated by the signal-to-noise ratio before and after filtering, signal entropy, and the model’s mean square error (MSE) value. It is found that over a wide range of high noise from –12 dB to –7.5 dB, the common threshold method provides more effective noise filtering than other methods. Keywords: discrete wavelet analysis, threshold method, radar signal, entropy, threshold function