TIME-VARYING MATCHED-FILTERS

We examine a generalized matched-filter problem in which the interfere nce is a nonstationary process generated by passing white noise throug h a general linear time-varying filter. First a matched filter is cons tructed by transforming the problem into an equivalent formulation inv olving stationary interference and a time-varying propagation channel. Whereas the response of a time-invariant matched filter is sampled at its peak, the response of this time-varying matched filter is normali zed before sampling to account for variations in the signal power. Nex t a matched filter is constructed using a spectral characterization of the nonstationary interference. This construction is then used to for mulate a simplified solution for the case where the rate of variation in the nonstationary interference is sufficiently small. The different solutions are illustrated by a numerical example.