基于正交小波包的瞬时频率检测

本分析了瞬时信号及噪声的时频特性和小波变换特性。根据小波包变换具有的优良时频分析能力，通过引入阈值熵来定量地描述瞬时信号在时频空间中的分布。理论分析和实验结果表明本方法简单，可靠，且易于检测。

Detection of Instantaneous Frequency Based on Orthogonal Wavelet Packet

This paper discusses the time frequency features and wavelet transform features of instantaneous signals and noise. According to the excellent time frequency localization analysis properties of the wavelet packet, this paper discribes the distribution of the instantaneous signal quantitatively in time frequency space by introducing the threshold entropy. Then proposes a method to detect the arrival time of instantaneous signal and the frequency composition under strong noise background. Theoretical analysis and the results of experiments both indicate that this method is simple, reliable and easy to be achieved.