Research On Detection Performance Of Underwater Acoustic System In Complex Water Environment

Detection performance is one of the most important performance of the underwater acoustic system, and is closely related to the parameters of the sonar system, underwater environment and target characteristics. Due to the influence of random factors such as the nature and geographical conditions, the complex water environment of shallow water, is the chief factor of the system detection performance.The sea trial data has shown that, the detection performance changes greatly in different water conditions. As one of the primary target of the detection performance, the range directly reflects the detection performance of the system. Studying the detection performance of underwater acoustic system in complex water environment, on the one hand, can provide reference for system environment matching design, on the other hand, can be of great significance in system optimization use, and increasing the efficiency of the system.Therefore, the research on detection performance of the underwater acoustic system in complex water environment, and achieving range forecast on the spot has important theoretical significance and engineering application value.This paper firstly uses the shallow water high-frequency acoustic field model, to calculate the impulse response of coherence-multipath channel,secondly establishes the point target echo model, combined with the active sonar detection model, builds active sonar range forecast model. By using of the measured sound velocity and detection result data,the MATLAB simulation is carried out to verify these models.Finally by means of the range forecast model and the measured sound velocity data of typical seasons in China’s three sea area, On the surface target, the underwater target cases respectively, the influence of the sound source depth,sound velocity gradient on two kinds of common active sonar signal detection range is explored. Through the above research, this paper gets the following results:(1)Using Eigen ray information to obtain channel impulse response, combined with the target information, the point target echo model is established, and the validity of the model is validated by the measured data.(2)Based on the point target echo model and the active sonar signal detection model, the range forecast model is put forward, which can reflect the relation among the system, the channel, and the target.(3)Based on the range forecast model and the measured data, on the sea surface target, the underwater target cases respectively, the influence of the sound source depth and the sound velocity gradient on detection range of the linear frequency modulation and single frequency pulse signal within intermediate frequency is explored.(4)On the basis of the analysis results, the reference opinions on optimization use of the system are put forward.The research achievements in this paper, can offer theoretical reference in the active sonar range forecast on the spot.