Study Of Passive Positioning Method With A Single Vector Hydrophone

Underwater acoustic positioning method has been a hot topic in underwater acoustic engineering research for a long time. As the single hydrophone has no direction-finding capacity,the acoustic positioning technology is usually achieved with an array of multiple hydrophones. A single vector hydrophone can measure the sound pressure and particle velocity information of the same point in the sound field synchronously,and direction estimation of target can be done by a single measurement. When the target moves at a regular,its location relative to the vector hydrophone is possible to be computed through multiple measurements. As a result, direction estimation, passive positioning method with a single vector hydrophone and its application are discussed and studied in the thesis, the specific works are as follows:Firstly, the methods of direction estimation with a single vector hydrophone are studied.Two methods, including weighted histogram method and histogram method are listed and factors that affect their performance are analyzed in the thesis. Some cautions of the methods in practical are also pointed out. What's more, the direction estimation based on envelope spectrum, in which the problem of ambiguous is solved and the directions of multiple targets can be estimated, is given in the thesis. The sea trial data processing validates the methods.Secondly, two passive positioning methods with a single vector hydrophone are given.One is the direction-only passive positioning method, which only utilizes relative position between the measuring points and ranges between the measuring points and vector hydrophone to determine the relative position between the measurement points and the vector hydrophone. The other one is the passive positioning method of a target whose locus is in a straight line and whose velocity is constant. The velocity is solved via the estimation of the frequency estimation or GPS difference. Then positioning result is achieved by combing the velocity estimation and direction estimation. The simulation and sea trial data processing validate the methods.Finally, the directivity of noise radiated from surface ship is estimated combining passive positioning method with a single vector hydrophone. The methods of estimating the directivity of strong lines and envelope spectrum lines are also given in the thesis. Some interesting results are derived by processing the sea trial data.