基于周期谱包络的线性调频信号特征参数估计

线性调频信号是二阶循环平稳信号,其周期谱幅度包含了信号的最小载频、最大载频以及调制斜率等信息。本文提出了利用非零循环频率处谱峰的位置与大小估计这三个参数的算法,该算法不需要信号参数的先验信息;对参数的估计是在非零循环频率处进行一维搜索,可减小平稳噪声和干扰的影响,适用于低信噪比情况,且避免了多维搜索;文中给出了算法的实现过程,分析了其估计性能,最后进行了计算机仿真实验。

Characteristic Parameter Estimation of Chirp Signal Based on Cyclic Spectrum Amplitude

Chirp signal is a second order cyclostationary signal, where the information of the minimum carrier frequency, the maximum carrier frequency and modulated slope is included in the amplitude of cyclic spectrum. A parameter estimation algorithm of chirp signal which makes use of the position and magnitude of non zero cyclic spectral peaks to estimate the three parameters is presented. This algorithm can implement estimation without a prior knowledge of signal parameters. This algorithm is suit for the estimation of low input SNR, which can weaken the affection of stationary noise and interference by searching in non zero cyclic frequency. In addition, this algorithm is more efficient by reducing multi dimensional search to a single dimensional search. In this paper, the realization of the estimation algorithm is given and the performance of parameter estimation is analyzed. Finally one computer simulation is offered.