High Resolution Beamforming And Azimuth Estimation Methods Based On Cylindrical Arrays

Underwater target noise detection is of great value for the study of the spatial distribution of ship noise sources and the reduction of ship radiation noise.The spatial resolution and azimuth estimation of multi-radiation noise sources for underwater near-field targets is studied.Due to the characteristics of underwater acoustic channels and underwater sound sources,the use of a single hydrophone often fails to provide accurate measurement results.Similarly,even with hydrophone arrays,the high resolution performance of underwater targets under conventional methods cannot meet actual needs.The MUSIC high-resolution beamforming algorithm is mainly used to simulate the high-resolution performance of the MUSIC algorithm with a hydrophone cylinder array,and real data is collected in the lake test and sea test to verify the performance characteristics.The research status of beamforming technology and ship radiation noise measurement is introduced.The characteristics and measurement methods of shallow sea sound channels,underwater radiation source noise,and beamforming and other related theories are analyzed.On this basis,aiming at the deficiency of current radiated noise measurement,a solution to the measurement of high resolution radiation noise using a cylindrical array is proposed.The performance of high-resolution azimuth estimation of cylindrical array with MUSIC algorithm is verified by computer simulation method,and the performance of conventional beamforming CBF and super-directional SPD beamforming algorithm is analyzed and compared.In order to solve the sound source-level estimation of hull multi-sources,a new method of high-resolution sound source level estimation using MUSIC algorithm is proposed and its performance is simulated.Finally,the lake test and sea test is conducted to verify the performance of the algorithm.The verification results show that the MUSIC algorithm can distinguish the two targets with the minimum opening angle of about 6° in the simulation and experimental data,and has a great advantage compared with CBF and SPD.Using the high resolution capability of the MUSIC method on the basis of conventional beamforming,it is possible to estimate the sound source level separately for dual targets that cannot be resolved by conventional beamforming methods.