海水中声波信号检测算法研究

Research on acoustic signal detection algorithms in seawater

海水内部复杂的噪声环境以及声波发射端和接收端的相对运动所导致的多普勒效应,使海水中表征有用信息的声波信号信噪比低,且声波频率会产生偏移.针对这一问题,建立了海水中的声波传输模型,并以适合于海底低功耗、微处理器实现的双频声波信号的实时检测算法为研究对象,通过仿真实验对比了相关分析、频谱分析、功率谱密度分析以及短时傅里叶变换等信号检测算法的性能,为海水中声波信号检测系统的实现提供了参考.

It has the characteristics of relatively small attenuation and long propagation distance.However,the complicated environment in seawater brings many difficulties to the acoustic signals detection,such as the complexity of noise interference under seawater,the relatively low signal-to-noise ratio;the Doppler effect caused by the relative movement of the transmitter and the receiver.Focusing on the real-time detection of dual frequency characteristic acoustic signal by MPU with low plow power consumption,a transmission model of the acoustic signal in seawater is created firstly.Then four different detecting algorithms,correlation analysis,fourier transform analysis,power spectrum density analysis and short-time fourier transform analysis are compared by MATLAB simulation.Finally,a conclusion is given as the reference of the implementation of an acoustic signal detection system in seawater.