基于多窗口时频重排的非线性调频信号时频结构分析方法

Time-Frequency Structure Analysis of Nonlinear Frequency Modulation Signal Based on Multiple Window Time-Frequency Reassignment

基于时频重排的高时频聚集性和多窗口分析方法低方差、高分辨率等优点,提出一种基于多窗口时频重排的非线性调频信号时频结构分析方法.该算法结合时频重排和多窗口分析方法,降低由重排振荡和噪声引起的波动,保持时频重排的高时频聚集性,同时清楚地展示了非线性调频信号的频率调制规律.仿真实验结果证实该方法对两个相距很近的二次多项式调频信号和实际的蝙蝠声纳信号都非常有效.

Based on the sharp localization of reassignment and the low multiple window, a time-frequency structure analysis method, which structure of nonlinear frequency modulation chirp signals variance, high resolution of analyses the time-frequency , is proposed. This algorithm consists of combining time-frequency reassignment with multiple window, which not only reduces the fluctuations caused by noise and reassignment but also maintains a high localization of time-frequency reassignment. The algorithm clearly displays the frequency modulation law of the nonlinear frequency modulation chirp signals at the same time. The simulational results demonstrate the validity of this method for both the two nearly closed quadratic frequency modulation signals and bat sonar signal.