Adaptive signal detection on the background clutter

Abstract

Introduction. The article poses the problem of optimal detection of coherent-pulsed signals of moving targets against a background of clutter with a priori uncertainty of the signals and clutter parameters. The aim of the article is the synthesis and analysis of adaptive signal detection systems. Synthesis of adaptive detection algorithm. The algorithm for optimal detection of signals against a background of clutter is determined by calculating the likelihood ratio. The implementation of the obtained algorithm for optimal linear filtering is assumed on the basis of the adaptive matrix filter and the non-adaptive multichannel filter. Evaluation of the signal phase. A quasi-optimal algorithm for estimating the Doppler phase of the signal from the output samples of the adaptive matrix filter is synthesized. Modeling on a PC has established that the asymptotic properties of the obtained estimates are acceptable for their use in adaptive signal accumulation. Synthesis of the adaptive detection system. A detection algorithm with adaptive signal accumulation is proposed. This algorithm combines adaptation to the clutter parameters and to the Doppler phase of the signal. A block diagram of the adaptive signal detection system is given. Analysis of the adaptive detection system. The optimal size of the detuning of Doppler channels of adaptive signal accumulation is determined by PC simulation. It is established that with an allowable loss level of up to 2 dB, the number of Doppler channels can be reduced by a factor of four. Conclusion. The use of Doppler signal estimation in detection systems with adaptive signal accumulation allows reducing the number of Doppler channels or, with the same number of Doppler channels, detuning between channels, eliminating interchannel losses.