一种水下目标辐射噪声调制特征提取方法

水下目标辐射噪声的调制信号携带许多重要特征信息,本文在现代信号处理理论的基础上对其调制特征提取方法进行了探讨。首先,利用小波变换和多分辨率分析理论,提取水下目标辐射噪声的调制包络;然后选取具有明显调制特征的特定频段数据对其进行112维谱分析,得到了辐射噪声的谐波信息。该方法结合小波变换与高阶谱理论对调制谱进行提取,可同时利用小波的消噪和高阶谱对高斯噪声的天然抑制性。对实测噪声数据进行的仿真结果表明,该方法可以有效提取噪声中的动态调制信息且抗噪性良好,具有很好的应用前景。

A Method for Modulation Feature Extraction of Underwater Target Radiated Noise

Modulated signal of underwater target radiated noise contains much important feature information.According to modern signal processing theory,a method for modulation feature extraction of the radiated noise is discussed.First,by using wavelet transform and multiresolution analyses,the modulated envelop of underwater target radiated noise is extracted.Then,the dynamic modulation is analyzed by one and a half dimensional spectrum and the harmonic information is obtained.The method can simultaneously make use of the noise elimination performance of wavelet and the natural restraint to Gaussian noise of higher order spectrum.The simulation result of real radiated noise data indicates that the method can extract the dynamic modulated feature from radiated noise effectively with an excellent anti-noise property.