Reverberation Intensity Prediction In Deep Ocean Based On Ray Theory

As reverberation is the main interference in active sonar system, the prediction of reverberation is a popular area in underwater acoustic field. Therefore,the prediction methods possess a very important value in scientific research in theoretical and practical engineering.In the ocean space,a large number of scattered bodies will be reallocated to the acoustic energy, and the scattered wave in the space is formed at the receiving point. So the reverberation contains too much information of scattered bodies. As reverberation cannot arise without active sonar works, so there are a lot of similar characteristics in the frequency spectrum between reverberation and transmitted signal, the reverberation contains much information of the source. This also raises the difficulty in separating target echo from reverberation interference. Consequently, some methods which are commonly used to increase signal to noise ratio cannot be used to suppress the reverberation.In this paper, reverberation strength forecast model in the deep sea environment is established with Gaussian beams method based on ray acoustics for National deep-sea development strategy. In addition, process of reverberation important scattering process is analyzed in detail. In particular, considered monostatic and bistatic sonar system, two different reverberation models are established and analyzed respectively. With these models,three different reverberation (bottom reverberation, the surface reverberation and volume reverberation) can be forecasted. At the same time, the attenuation law of reverberation and reasons are analyzed. The study shows that compared with surface reverberation and bottom reverberation,volume reverberation is the main interference in deep sea environment. In addition, because of the distance and high directivity, the performance of bistatic sonar system is much better than monostatic on the aspects of restrain reverberation.