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该文研究讨论一种利用小波分析理论对功率谱进行二次处理的方法.论文首先介绍了这种方法的应用背景,给出了舰船辐射噪声功率的结构.在简明扼要地介绍了小波理论的有关基础知识,给出线谱的数学解释并分析了它在尺度分解中的特点之后,论文基于多尺度分析与奇异性信号检测的理论,对信号的功率谱做尺度分解,利用线谱的奇异性捕捉舰船辐射噪声功率谱中的线谱分量.由实船辐射噪声信号的分析结果我们看到,这种二次处理的方法不仅可以准确定位低信噪比的线谱,而且可以同时提取所有可能的线谱信号.“,”This paper discusses the reprocessing method of analyzing the power spectrum of signal using wavelet theory. Firstly, the application background of this method is introduced, and the structure of the powerspectrum of ship-radiated noise (SNR) too. Then, for convenience of discussing engineering problems, the basic knowledge of the wavelet theory is concisely introduced. Considering the mathematical interpretation, the paper ana- lyzes the properties of the be of spectrum with the idea of multiscale. The new method of detecting the lines of spectrum from SRN is discussed. It detects the the by means of their singularity in the power spectrum. The theories of the multiscale analysis and the detection of singular signal are the fundament of the reprocessing method. By making use of the data of the ship noise, we can draw a conclusion that not only the low signal--to--noise rate (SNR) lines with the precise frequencies but also all possible be can be detected with the reprocessing method.