SIGNAL PROCESSING ALGORITHM IN MULTICHANNEL RADAR FOR RESCUERS

Abstract

Subject and Purpose. The subject of the research is a system of coherent digital processing of radar signals such that includes a number of spatially spaced receiving points and is designed to detect moving objects hidden behind optically opaque obstacles. The aim of the work is to synthesize an optimal, in the sense of a minimum Bayesian risk average, signal structure in the processing system. The system performance is evaluated and recommendations as to the choice of signal preprocessing system parameters are developed. Methods and Methodology of the work are based on the analysis of probabilistic characteristics of the useful and interference signals and seek to synthesize an algorithm for processing observed signal implementations according to a single quality criterion of a minimum average loss from incorrect decisions. The task of detection and estimation of moving objects in terms of their number and angular coordinates is formulated as a statistical problem. The angular resolution algorithm for point targets is built on the principle of statistical hypothesis testing. The a priori information about the characteristics of useful and interference signals during the target movement and, also, about the target probabilistic properties allows a procedure of signal processing to be built through the spatial synthesis of the observation system aperture, offering a resolution exceeding the energy limiting resolution. Results. Analytical relations have been obtained for the joint procedure of signal detection and arrival angle measurement. The estimated angular positions of the targets are used in the aperture synthesis algorithm. It has been shown that the real-time aperture synthesis is possible in the case of relatively high signal-to-noise ratios and linear and unidirectional movement of targets. Conclusions. A two-channel algorithm for monitoring moving targets has been developed. Based on the a priori information about the nature of target movement and on the estimates of angular positions and numbers of the targets, a passive synthesis procedure for the observation system aperture has been constructed. Recommendations have been developed for algorithm implementations in real time.

Keywords

• algorithm
• bayesian risk
• criterion
• discrete processing
• radar station
• sampling
• sampling frequency
• spectral function
• white noise