Research On Noise Sources Near-field Location Method Based On The Passive Time Reversal Mirror Technique

The submarine radiated noise is the main target of detecting and tracking the submarineby various sonar equipments. It impacts the stealth performance of submarine and thesubmarine combat capability. Studying the noise sources location techniques, identifying themain noise sources and taking some measures of reducing noise and vibration are powerfulmethods to reduce the submarine radiated noise. In recent years, with the improvement of thelevel of sound stealth technology, the submarine radiated noise level is gradually reduced. Thetraditional far-field measurement method is difficult to obtain the effective source ofinformation, so it is important and significant to study the noise sources near-field locationtechnology.The multi-path effect exists in the marine and the wave dissemination rule is complex.Compared with the sound source radiation signal, the signal received by the receiver hasgenerated a great distortion, which will seriously affect the results of the noise sourceslocation. The technology of passive time reversal mirror takes into account the wavedissemination rule in the marine. It is an adaptive focusing method, which can overcome themulti-path effects. Based on the background of the measurement of the sound field in the pierenvironment, the paper studies the noise sources near-field location method based on thepassive time reversal time technology.Firstly this paper studies the noise sources near-field location method, which has thecapability of high resolution. Based on the method of CBF, the paper introduces some basicconcepts of the noise sources near-field location method. For the characteristics of submarineradiated noise, this paper discusses the noise sources near-field high resolution locationmethod based on the amplitude compensation. The results of simulation analysis prove thatthe amplitude compensation can improve the spatial resolution of the noise sources near-fieldfocusing beam forming method.For the multi-path effect in the marine, the passive time reversal mirror technology hasbeen brought into the method of noise sources location. After studying the basic theories ofocean ray acoustic, the paper establishes the channel function model in pier environment andreviews the basic theories of the passive time reversal mirror focused location method. On thebase of the above results, this paper provides a method of the noise sources near-field highresolution location based on the passive time reversal mirror, and the results of simulationanalysis prove its high-resolution ability to locate the low-band noise sources in shallow marine. Finally, the paper studies the influence factor that shore reflection in pierenvironment.The surface of actual submarine noise source radiating is cylinder, so the cylinder noisesources location method is studied in this paper. Firstly it discusses the cylinder noise sourcesnear-field location method and cylinder passive time reversal mirror focused location method,and then the superiority of the cylinder high resolution location method based on the passivetime reversal mirror is proved by the result of simulation analysis. At last, the influence ofshore reflection is considered into it.