Research On Passive Detection Of Ship Noise Signal Based On Two Linear Arrays

The detection of underwater acoustic signals is an important direction of underwater acoustic technology,and it is also a research hotspot of underwater acoustic technology.It plays an important role in both military and civilian technologies.This thesis starts with the construction of the array-level signal noise model and studies the passive detection method of wide-band signals in a bi-level linear array.First,the mathematical model of the array elementary received signal is given.Based on the mechanism of noise generation in the marine environment and the generation mechanism of radiated noise from ships,a mathematical model from propagation theory was used for the elementary signals of the marine environment noise and ship radiation noise received by the array.During the simulation process,the spatial correlation characteristics of the noise were used.Secondly,the passive line spectrum signal detection method of single linear array is studied by using adaptive line spectral enhancement and deconvolution method.The effect of ALE on detection performance was simulated and analyzed from the principle of adaptive line spectral enhancer.A line spectrum detection method based on adaptive line spectral booster beamforming is given.Then,on the basis of robust conventional beamforming,a deconvolution beamforming method is introduced based on array manifolds.Due to the increased resolution,multi-target resolution performance can be improved.In the case of multi-target detection,the performance of deconvolution beamforming is compared with that of conventional beamforming.The multi-target resolution performance is simulated by changing the array parameters,iteration times,and signal-to-noise ratio.The robustness of the deconvolution algorithm was simulated at the same time.Finally,the passive detection method of radiated noise signals of dual-line array is studied.From the related processing of spatial dual-hydrophone receiver signals,the spectral information of radiation noise is extracted and the azimuth angle of the target is estimated.On this basis,it is extended to a bi-level linear array.Using the spatial filtering capability of beamforming,the beam among each array is processed in correlation to obtain the detection results of the target and separate characteristics of multi-vessel targets.