一种新的基于分数阶Fourier变换的线性调频信号的参数估计方法

摘要

目前，采用分数阶 Fourier 变换算法对线性调频(LFM)信号实现参数估计的研究中，总假定观测信号的时长等于LFM信号的脉冲宽度，但这一假设在实际中难以得到保证，故原有参数估计算法具有极大的应用局限性。本文通过对实际观测信号形式进行分析，推导出原有参数估计算法的估计误差，在此基础之上给出了一种新的实用的线性调频信号参数估计方法。仿真结果表明新的参数估计方法可打破原有应用局限，对实际观测信号实现有效的参数估计。%Currently, the realization of parameter estimation of LFM signal using fractional Fourier Transform is based on the assumption that the sampling duration of the practical signal is equal to the time duration of the LFM signal. Actually, this assumption is not reasonable and there is limitation in application of the existing parameter estimation method. On the basis of analysis of the practical signal form, this paper derives the estimation error of the existing parameter estimation method and then proposed a novel parameter estimation method. Simulation results verify that the new method is effective.