Adaptive filtering of matched-filter data

摘要

An adaptive processor which uses the successive range and Doppler outputs of a conventional matched-filter to improve the signal-to-noise ratio for non white noise/clutter. The adaptive processor minimizes the output for a given range and Doppler cell with the constraint that the response to signals returning with specified range and Doppler offsets, with respect to the center of the range-Doppler cell, each have specified values. Weights are derived which can be applied to range-Doppler outputs in the neighborhood of the range-Doppler cell to minimize its output subject to the constraints. The weights depend on an estimate of the cross-covariance matrix of the various outputs of the range-Doppler cells that are to be weighted. The constraint parameters are specified in terms of the ambiguity function of the transmitted waveform. Synthetically generated covariance matrices or combinations of measured and synthetic matrices can also be used to produce desired modifications to the resulting range-Doppler response of the adapted process.