关键词: 振动与波, 多项式相位信号, 非线性调频小波变换, 多项式核函数, 时频分析, 瞬时频率估计

Abstract: Nonlinear chirplet transform, a new parametric method for time-frequency analysis was proposed by replacing the linear chirp kernel by a nonlinear polynomial kernel. By choosing the proper kernel characteristic parameters, the nonlinear chirplet transform can render a time frequency distribution of excellent concentration for signals whose instantaneous frequency trajectory is an arbitrary function of time. In this paper, the polynomial chirplet transform was applied to estimate the polynomial phase signals with arbitrary order. As the performance of the nonlinear chirplet transform highly depends on the kernel characteristic parameters, an algorithm to evaluate these parameters was developed in order to estimate the instantaneous frequency and the phase parameters of the polynomial phase signal. The effectiveness of the algorithm was validated by analyzing the signals from numerical simulation.

Key words: vibration and wave, polynomial phase signal, nonlinear chirplet transform, polynomial kernel function, time frequency analysis, instantaneous frequency estimation