The Application Of Lattice Structure Adaptive Filters To Clutter Suppression For Scanning Radar

This paper describes the use of an adaptive filter to enhance the detection of moving targets in the presence of clutter. The scanning and pulsing rates of a typical surveillance radar produce, within each resolution cell, a time-series of samples at a given range, resulting from the consecutive pulses. In the case of coherent radar, this time-series corresponds to the Doppler spectrum of that resolution cell, containing radial velocity information on both targets and clutter within the cell. An adaptive filter can be used to enhance the target signal over the clutter signal by matching the clutter spectrum, thus whitening the filter output, so that only the target's spectral components stand out. It is possible for the filter to discriminate between the clutter spectrum and the target spectrum because clutter is generally a diffuse source, spread over many adjacent cells, while the target is generally a point source, occupying a single cell.