Research On Detection And Location Technology Of Bistatic Sonar Based On Direct Wave Suppression

Bistatic sonar has the advantages of good concealment performance,strong antiinterference ability,and easy implementation.Nowadays it has become a hot issue in the field of detection,localization,tracking and so on.Based on bistatic sonar direct wave suppression problems,bistatic sonar system in target detection and location technology has been studied in the paper.Firstly,the research on the side lobe suppression of direct wave interference is carried out.The paper proposes two algorithms for suppressing direct wave interference: one is spatial smoothing MVDR algorithm,and the other is deconvolution beamforming algorithm.The resolution,anti-interference performance and robustness of the two algorithms are compared and studied.The results show that deconvolution beamforming has obvious advantages in antiinterference performance and algorithm robustness.Secondly,research is conducted on the detection of constant false alarms of underwater acoustic signals.The performance of each detector under the background of uniform noise and multi-target interference is compared and analyzed.The results show that: under the uniform noise background,the detection performance of the CA-CFAR detector is the best;under the interference background,the detection performance of the SO and OS-CFAR under the interference background is better.Comparing with SO,when there are interference target both in front and back sliding window,the detection ability of the OS in a multi-target background is better.Finally,the research is focused on the problem of bistatic sonar target location and solution.Three positioning algorithms based on the three observations of the observation time,the observation angle of the transmitting station,and the observation angle of the receiving station in bistatic two-dimensional positioning are studied,the positioning errors are analyzed,and the corresponding GDOP calculation formula is derived.The results show that the proposed TBL algorithm based on all observations has better positioning accuracy than the LOL algorithm,and improves the positioning accuracy at the baseline compared to the TOL algorithm.The algorithm is used to complete the test data verification.