Research On Self-noise Suppression Method Of Autonomous Underwater Vehicle

The mobility and autonomy of Autonomous Underwater Vehicles(Autonomous Underwater Vehicles,AUV)enable them to operate autonomously in larger areas without intervention,and they have broad application prospects in the field of ocean engineering.AUV equipped with a hydrophone array can expand the detection range of underwater targets and improve detection performance through flexible movement and position optimization of the AUV.However,due to the influence of the array aperture and platform size,the self-noise of the AUV platform as a near-field interference source has a serious impact on its detection performance.Therefore,it is of great practical significance to carry out AUV self-noise suppression research.Aiming at the problem of self-noise suppression on aircraft platforms,the paper conducts research from three directions: beam domain,wavenumber domain,and adaptive filtering.In the beam domain,the inverse beamforming and null steering beamforming,which are often used in tow ship noise suppression,are applied to AUV self-noise suppression;in the wavenumber domain,a self-noise suppression method based on wave number domain filtering is proposed.This method mainly uses the difference between the hydrophone array receiving signal propagating through the water body and the aircraft body,and the difference in the signal in the wave number domain is filtered through the wave number domain.To reduce the interference of the body’s self-noise;in terms of adaptive filtering,for the autonomous underwater vehicle system equipped with a towed array,the end-fire direction beamforming output is used as the reference signal,Self-noise suppression is achieved through adaptive cancellation.At the end of the thesis,the above three types of methods are verified by sea trials.First,the sea trial hardware and the software systems are introduced,including the four-element linear array and the sixteen-element towed array and online target detection software and hardware system and the joint test process.Then introduced the sea trial process and sea trial data collection process.Finally,the sea trial data is used to verify the above three types of methods,and the performance and existing problems of each algorithm are analyzed.