水下蛙人被动探测测向实验研究

The passive direction finding experimental research for underwater swimmers

为了对携带开式呼吸器的水下蛙人进行被动探测,本文采用四个水听器组成的十字阵在浅海水域对水下开式蛙人进行了被动探测、测向实验。结果表明:蛙人辐射噪声具有周期性特征,其周期与蛙人的呼吸频率有关;另外,蛙人呼吸辐射噪声具有显著频带,并且其频带与蛙人携带的呼吸器有关。根据蛙人辐射噪声的显著频带和周期性特征,设计信号处理算法实现了对蛙人的被动声学探测识别。使用互相关方法处理一对水听器的接收信号,可以确定蛙人的方位,但是根据理论分析会出现一个假方位。对比十字阵中两对水听器的测向结果可确定蛙人的准确方位。

The purpose of this work is to detect and localize underwater swimmers. This paper presented a four-hydrophone array to detect underwater swimmers carrying open breathing apparatus. The detection and location experiments of underwater swimmers are carried out in shallow sea. The experimental results indicate that the radiation noise of divers has cyclical characteristics, and its period depends on the divers breathing frequency. In addition, the radiated noise of underwater divers has significant frequency band, and the frequency band is related to the breathing apparatus. According to periodic characteristics of radiated noise and significant frequency band, a signal processing algorithm was designed to detect and identify underwater divers. Using cross-correlation method for processing the received acoustic signals of a pair of hydrophones can determine the position of underwater divers, but there will be a false orientation based on theoretical analysis.Fusion two lateral results from the cross array can determine the exact location of underwater divers.