伸缩窗口短时Fourier分析

Short-Time-Fourier Analysis Based on Dilating Window

在短时 Fourier变换 ( STFT)的基础上 ,通过对窗函数在时间尺度上引入伸缩变换 ,从而获得一个在相空间可变的窗口 (即可调时 -频窗 ) ,实现时频分辨率随信号频率变化自动可调 ,克服STFT分析所有频率窗口的大小形状固定不变的缺陷 ,为非平稳信号的处理提供了强有力的工具。

This paper obtains a changeable window in the time frequency domain by introducing dilating transformation to the window function on the time scale on the basis of short time Fourier transformation, realizes automatically adjusting the time frequency solution with the changes of the signal frequency, overcomes the limitation of the STFT that utilizes the same size and shape window to analysis all frequencies and therefore provides a powerful tool for the non stationary stochastic signal processing.