高聚焦时频分析算法研究

乔丽红 卫彬 杨铁军 秦瑶

摘  要： 时频分析技术是研究非平稳信号时频分布的重要手段，但传统的时频分析技术无法精确地反映信号的时频分布特点。文中主要介绍了三种高聚焦时频分析技术：小波变换（WT）、同步挤压小波变换（SSWT）、CWT?based ConceFT 。首先分别阐述了以上三种高聚焦时频分析技术的原理，然后将这三种高聚焦时频分析方法应用于非平稳信号，并比较它们的时频分析效果。结果表明，SSWT和CWT?based ConceFT明显提高了小波变换的时频分辨率，小波变换和同步挤压小波变换的噪声鲁棒性较差，CWT?based ConceFT的噪声鲁棒性较好。

关键词： 时频分析; 小波变换; 同步挤压小波变换; CWT?based ConceFT; 时频分辨率; 噪声鲁棒性

中图分类号： TN911.6?34                        文献标识码： A                         文章编号： 1004?373X（2020）13?0040?04

Study on well?focusing time?frequency analysis algorithm

QIAO Lihong1， 2， WEI Bin1， YANG Tiejun1， QIN Yao1

（1. College of Information Science and Engineering， Henan University of Technology， Zhengzhou 450001， China;

2. Key Laboratory of Food Information Processing and Control， Ministry of Education， Zhengzhou 450001， China）

Abstract： The time?frequency analysis technology is an important means to study the time?frequency distribution of non?stationary signals， but the traditional time?frequency analysis technology cannot accurately reflect the characteristics of time?frequency distribution of signals. In this paper， three well?focusing time?frequency analysis techniques， e.g. wavelet transform （WT）， synchrosqueezed wavelet transform （SSWT）， CWT?based concentration of frequency and time （CWT?based ConceFT） are introduced. The principles of the three well?focusing time?frequency analysis techniques are expounded respectively. The three technologies were applied to non?stationary signals for comparing their time?frequency analysis effects. The experiment results show SSWT and CWT?based ConceFT have improved the time?frequency resolution of wavelet transform obviously， and the noise robustness of CWT?based ConceFT is better than that of WT and SSWT.

Keywords： time?frequency analysis; wavelet transform; synchrosqueezed wavelet transform; CWT?based ConceFT; time?frequency resolution; noise robustness