广义S变换及其时频滤波  

Generalized S Transform and Its Time-Frequency Filtering

作　　者：陈学华[1] 贺振华[1] 黄德济[1] 

机构地区：[1]成都理工大学信息工程学院

出　　处：《信号处理》2008年第1期28-31,共4页Journal of Signal Processing

基　　金：国家自然科学基金项目(40474044)资助;四川省教育厅资助科研项目(ZY0010)

摘　　要：首先从基于高斯窗函数的短时傅里叶变换推导出了一种广义S变换,分析了它与S变换及小波变换的关系,给出了它的运算实现。理论分析与仿真实验表明,广义S变换的时频窗口不仅能够随着频率尺度自适应地调整,而且克服了S变换中时窗函数的变化趋势固定不变的问题,使广义S变换在应用中具有更高的实用性和灵活性。利用其高质量的时频分布。在时频平面中设计时频滤波器,用于非平稳信号中特定信号分量的提取,展示了广义S变换在这一应用中的有效性。A Generalized S transform （GST） is derived theoretically from the short-time Fourier transform （STFI＇） with Gaussian window in the paper. The paper analyzes the relationship between GST and S transform （ST） and wavelet transform （WT）. The numerical implementation of GST is introduced later. The detailed analyses both in theory and in the simulation indicate that the time-frequency window of GST can not only varying adaptively with the frequency, but also avoid the unchangeable and fixed varying pattern of the window in ST. GST possesses adjustable time-frequency resolution with higher practicability and adaptability than ST in actual application. A time-frequency filter on the time-frequency plane based on its excellent time-frequency distribution is presented,which is used to extract specific signal components and filter noise on the particular time-frequency plane. The simulation demonstrates that the filter based on GST is effective in signal extracting.

关 键 词：时频分析 S变换 广义S变换 时频滤波器 

分 类 号：TN911.72[电子电信—通信与信息系统] P631.443[电子电信—信息与通信工程]