Towed array sonar fixed azimuth large interference source cancellation method and system

Abstract

The invention provides a towed array sonar fixed azimuth large interference source cancellation method and a system. The method comprises steps: 101) beam-forming processing is carried out on signals received by towed array elements to obtain corresponding beam space signals of a beam Bi in a theta azimuth; 102) a reconstruction strategy is adopted to obtain interference time domain signals of interference in the theta azimuth in each array element according to the beam space signals; 103) subtraction is carried out between signals actually received by each array element and interference time domain signals of interference in the theta azimuth, and signals of each array element cancelling interference at the theta azimuth is obtained; and 104) the above steps are repeated on interference at another theta<j> azimuth until influences of interference signals from each azimuth on actually-received signals of each array element of the towed array can be cancelled. The reconstruction strategy is that the zeroth array element in the towed array serves as reference and pre delay is carried out on beam space signals of the beam where interference is located according to the delay amount of each array element.

Description

technical field [0001] The invention relates to an interference suppression technology in array signal processing, in particular to a method and system for canceling a large interference source with a fixed azimuth of a towed line array sonar. Background technique [0002] Since the towed line array sonar is far away from the towed platform, the interference from the own ship's noise is relatively small, so it is often used to detect weak targets in water such as submarines. However, in the actual working environment, there are often strong targets such as large-tonnage surface ships. These targets have high radiation noise levels. When they exist in the same sea area, the receiving signal-to-noise ratio of the towed line array sonar equipment for weak targets will be greatly reduced. It is very difficult for target detection. [0003] At present, there have been relatively systematic studies on the cancellation method of this kind of towed line array sonar's own ship noise...

AI Technical Summary

Problems solved by technology

Therefore, most of the adaptive algorithms used to offset the noise of the own ship are not completely suitable for offsetting the interference of fixed large targets, and it is difficult to meet the actual application requirements

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