Research Of Sonar Parameter Optimization Technology With Matched Field Processing Passive Location

As the underwater acoustic technology develop the rapidly in recent years, matched field processing technology, a new type of passive locating methods, have been applied widely. There are more and more scholars and researchers develop an interest in matched field processing technology not only in China but also beyond the sea. They put a lot of attention in the study of the technology. In the field of underwater acoustic, matched field processing technology has been a front-burner issue.In this paper, based on the ray theory model, I accomplished a processing of passive positioning by the method of matched field. And I study the affect of working parameters such as integration time, working frequency band and depth of the hydrophone to the detection and matching performance of the system. Ray acoustics method was used in the matching process. The difference of time delay between the hydrophones was regarded as the cost function. In traditional matched field processing people always use a vertical array to receive the signal. However, as the posture of a vertical array of underwater will be affected by factors such as flow, route speed, there is no guarantee that the array is in a state of absolute vertical. At the same time the size of a vertical array will be limited to the depth of the water. Against the background of actual application, I use a horizontal array instead of a vertical array. By this way, the problem of limitation of the array size could be solved, at the same time also meet the receiving array of maneuverability.Based on the theory of ray acoustic model in the simulation, the signal from a source transmitted in a underwater acoustic channel will reach the hydrophone by a certain delay.Build up a grid structure in a scope of horizontal and depth and calculate the time delay difference of signal from a source at all the point on the grid between the benchmark hydrophone(sixth hydrophone) and others. And then set up a library of spread time difference as a Copy field library. At last the passive localization of sound source was realized by a coherent processing between the received time delay and copy related field,. By changing the array receiving depth, integral time and working frequency band working parameters study the influence of working parameter to operating range and matching results. By the result of the study, in different hydrological environment, we can set the working parameters reasonable so that the sonar can be in best state at the same time matching positioning accuracy and results can achieve the best.