WVD瞬时频率无偏估计研究

Unbiased Estimation of Instantaneous Frequency Using the Discrete WVD

通过检测Ｗｉｇｎｅｒ－Ｖｉｌｌｅ分布（ＷＶＤ）的峰值估计信号瞬时频率的方法（ＷＶＤ）频率估计器），对常幅、线性调频信号是无偏的。本文利用该估计器估计调幅－调频信号的瞬时频率时发现：如果信号满足Ｂｅｄｒｏｓｉａｎ定理，那么调幅对瞬时频率估计没有影响，从而，扩展了ＷＶＤ频率估计器的无偏条件。

The estimation of instantaneous frequency using the peak of the Wigner-Ville distribution(WVD) is unbiased for sinusoid of constant amplrtude and linear modulated frequency. In this paper we analyze the effects of the time-varying amplitude of a monocomponent signal on the WVD peak estimator,and find that if the modulated signal satisfies the Bedrosian theorem,the time-varying amplitude does not affect the estimation of instantaneous frequency.And the unbiased condition of the peak estimator is loosened.