基于STFT的舰船辐射噪声时-频分析与线谱提取  

Time-Frequency Analysis of Ship-Radiated Noise and Line Spectrum Extraction Based on STFT

作　　者：王晓峰[1] 王炳和[1] 相敬林[2] 

机构地区：[1]武警工程学院通信工程系 [2]西北工业大学航海工程学院,陕西西安710072

出　　处：《电声技术》2005年第11期61-63,71,共4页Audio Engineering

基　　金：国防科技"十五"重点预研项目(41303080301);陕西省自然科学基金项目(2001X28).

摘　　要：在分析舰船辐射噪声时频分布的基础上,改进了短时傅里叶变换(ShortTimeFourierTransform,STFT),使之更易于提取舰船辐射噪声中的特征线谱。首先在时域内对将要分析的数据进行低速率重采样,然后根据需要,选择不同宽度的高斯时窗函数作短时傅里叶变换,再用二重三次立方插值函数对分析结果进行平滑处理,得到了清晰的特征线谱。最后利用改进的时频方法对A型舰进行分析,结果表明:该方法对0～100Hz低频段特征线谱的提取效果很好,这为进一步分析其它舰型的低频段特征线谱提供了一种有效方法。Based on the analysis of the time-frequency distribution of the ship-radiated noise, short-time Fourier transform （STFT） is improved to extract the characteristic line spectrum from ship-radiated noise. First, the data of the ship-radiated noise is resampled at low rate in time domain. Second, according to the demands, the different width of Gaussian window can be chosen when STFT is calculated, and then the bicubic interpolation smoothness of the time-frequency distribution is done to get legible line spectrum. Finally a Model-A ship is analyzed by our method. The analysis results show that it is excellent to extract the line spectra between 0 and 100 Hz. The method offers an available approach to extract the characteristic line spectrum of other model of ships at low frequencies.

关 键 词：短时傅里叶变换 舰船辐射噪声 线谱 

分 类 号：TU112[建筑科学—建筑理论]