Chaff clutter filtering from radar data with Discrete Wavelet Transform

Abstract

Volume clutter is three dimensional and is usually measured per volume. This clutter has large volume and includes rain, chaff, birds, and insects. Birds, insects, and other flying particles are often referred to as angel clutter of biological clutter. Chaff clutter is introduced as passive jamming. Chaff clutter is a kind of man-made distributed clutter, typically made out of lightweight strips of reflecting material. Normally chaff clutter filtering is studied in frequency domain. Instead of the frequency domain, the wavelet analysis allows a time-scale domain in processing. The filter bank in this study utilizes discrete wavelet transform (DWT). DWT coefficients represent the results of a multi resolution analysis of the radar signal. We study the operation in the chaff clutter filtering using DWT, and present some results obtained using that filtering. The experiments were performed in MATLAB environment and data is real radar chaff clutter data from Finnish Air Force medium range air surveillance radar (low PRF). The objectives of this study were to develop the DWT based filtering system and test itpsilas operation to different chaff clutter and then to compare with results to those from the Fast Fourier Transform (FFT) based method.