改进非平稳信号的分析方法

研究了WVD和短时傅里叶变换两种时频分析方法的优势和局限性，从两种方法的定义出发，分析了两者间存在的联系，通过构造窗函数，提出一种改进的非平稳信号分析方法，并进行了相应的计算机仿真，结果表明信号的时频特性得到了改善，该方法还适用于多分量非平稳信号的分析。
关 键 词 时频分布; 非平稳信号; 调频信号; 参数估计

Abstract Wigner ville distribation and short time Fourier transform are the main time-frequency analysis methods. However, both of them have their advantages and limitations. On the base of the definition of the two transform, this paper analyzes the connection between them, then proposes an improved method through the construction of window function. Computer simulation shows the time-frequency character of signal is improved and the method is applicable to the analysis of multicomponent nonstationary signal.
Key words time-frequency distribution; nonstationary signal; frequency-modulated signal; parameter estimation