Passive Observation Of Underwater Target Motion Analysis Technology

In recent years,with the continuous development of underwater acoustic countermeasure technology,the theory of underwater target motion analysis has gradually become the focus of research and attention.In the problem of underwater target motion analysis,positioning time and positioning accuracy are two important indicators to measure the performance of the algorithm.Therefore,how to obtain higher precision solution results in a short time has become a hot topic for scholars at home and abroad.In order to improve the accuracy of passive sonar system in underwater target positioning,this paper focuses on the two key technologies of single array bearings-only target motion analysis and multi-information joint target motion analysis,and combines the actual needs of underwater target motion analysis to carry out for further study.In the single array bearings-only target motion analysis,the influence of the observer's maneuver scheme on the target observability is theoretically studied.The least square bearings-only target motion analysis(LS-BOTMA)algorithm is studied in detail and bias compensated least square bearings-only target motion analysis(BCLS-BOTMA)algorithm is proposed according to the feature that the state vector of the target which is calculated by LS-BOTMA algorithm is biased.The simulation results show that the calculating accuracy of the BCLS-BOTMA algorithm is higher than that of the LS-BOTMA algorithm.In the single array bearings-only target motion analysis,the observer must perform at least one maneuver in the observation process to meet the observable conditions of the target.Therefore,in order to overcome the observability requirements of the single array bearings-only target motion analysis,this paper studies Doppler-bearing target motion analysis and double arrays target motion analysis.In Doppler-bearing target motion analysis,the motion parameters of the target are calculated by using the Doppler shift and the bearing information which is measured by the observer when observer and target have a relative radial velocity.In double arrays target motion analysis,the motion parameters of the target are calculated by using the target's bearing information which is measured by double arrays at the same sampling time.The simulation results show that the target's state vector which is calculated by Doppler-bearing target motion analysis algorithm and double arrays target motion analysis algorithm gradually approaching the Cramer-Rao lower bound(CRLB)with the increase of time.Therefore,both algorithms can effectively estimate the state vector of the target.The experimental data processing results show that the accuracy of BCLS-BOTMA algorithm is higher than that of LS-BOTMA algorithm,and double arrays target motion analysis algorithm is asymptotically unbiased.