Research And Application Of Underwater Target Location Algorithm Based On Underwater Acoustic Sensor Network

In recent years,with the constant attention to ocean development strategy and the continuous and rapid development of marine economy,underwater target location(UTL)technology based on underwater acoustic sensor network(UASN)and its related applications have become a hot research topic in the marine field.UASN and UTL are the core issues in the development of marine technology.In the process of UTL,UASN is necessary to provide the communication basis and calculate the data such as distance,signal intensity and so on.Therefore,the communication ability of UASN and the choice of algorithm in the process of target location have a decisive effect on UTL.In this paper,the problem of communication between nodes of UASN is studied,and the reliability of communication between nodes of UASN is improved.On this basis,the problems such as imprecise range,low positioning precision,the difficultly of time synchronization and obstacle disturbance in the process of UTL are studied,and the solution is put forward and verified by experiments.Firstly,this paper introduces the research background and significance of the topic,and points out that the development of ocean-related technology has become the strategic work of most countries in the world at present.At the same time,the research status and application prospect of UASN and UTL technology are introduced.The features and characteristics of UASN in the process of theoretical research and practical application are summarized.Secondly,the organization structure and network characteristics of UASN,the characteristics of communication in UASN and the influence of these characteristics on the stability of underwater acoustic communication between networks are studied.In order to improve the stability of underwater acoustic communication between nodes in the network and ensure the reliable of communication between nodes,the inter-symbol interference caused by multipath and high dynamic underwater acoustic channel in the process of underwater acoustic communication is addressed.A restoration-equalization communication strategy based on decision-denoising-auto-encoding and Constant modulus algorithm(DAED-CMA)is proposed.Based on the feature learning ability of machine learning,the damaged data at the receiver is restored and reconstructed,and then sent to the adaptive equalizer for channel equalization.The simulation results show that the algorithm proposed in this paper is superior when faced with a large number of data loss problems in underwater acoustic communication.Then,under the condition that the USAN and the communication link are stable,this paper further studies the UTL.In the UTL process based on distance measurement,the first step needs to be carried out to measure the distance between the positioning node and the positioning target.A high-precision underwater distance measuring method based on the transmission and reception separation is proposed.The second step is to perform positioning and target position analysis on the basis of the distance measurement.In this paper,an asynchronous UTL method based on broadcast polling is proposed,and many experiments have been carried out on the distance measurement and the location method in the indoor pool,and the feasibility and reliability of the proposed method are proved.Finally,considering the obstacle interference in the process of UTL,the influence of obstacle on the location error of underwater target is analyzed.Taking the blocking noise caused by barrier as an example,the problems of multi-solution and no-solution are analyzed.In order to solve those problems,the least square support vector machine(LSSVM)algorithm is proposed to improve the anti-jamming ability of the position analytic algorithm to noise through off-line training of the model.Simulation results show that the proposed method is robust in the face of excessive measurement noise.