小波变换用于舰船辐射噪声调制信息检测

应用小波分析从舰船辐射噪声中提取调制信息,进行了仿真研究,供舰船识别利用.首先讨论了舰船辐射噪声的产生机理、构成和频率特性,指出螺旋桨噪声的振幅存在周期性调制.其次利用小波的多分辨分析的方法,在中低信噪比条件下,仿真实现了调制信号和舰船辐射噪声的分离.其结果表明,相对于传统DEMON分析,利用小波以及希尔伯特变换可以更快更好地提取舰船辐射噪声的调制信息.在水声信号处理领域,小波变换对于舰船调制信息提取是一种有效手段.

Detection modulated information from radiated noise of naval ships through wavelet transform

This paper applies wavelet analysis to extract modulated information from radiated noise of naval ships, which is useful in naval-ship recognition. Simulation research has been carried out. First, the generation mechanism, components and frequency characteristic of radiated noise of naval ships are studied. There exists periodical modulation for the amplitude of propeller noise. Second, by means of wavelet multi-resolution analysis, separating modulating signal from radiated noise of naval ships has been simulated and realized with moderate and low signal-to-noise rate. Compared with traditional DEMON analysis, the result shows that modulated information of radiated noise of naval ships can be extracted more quickly through wavelet and Hilbert transform. In the field of underwater acoustic signal processing, it is an effective way to extract modulated information of naval ships through wavelet transform.