基于线性调频Z变换的高性能频率估计  

Chirp Z transform-based high performance frequency estimation

作　　者：黄玉春[1] 黄载禄[1] 黄本雄[1] 徐书华[1] 

机构地区：[1]华中科技大学电子与信息工程系,湖北武汉430074

出　　处：《华中科技大学学报（自然科学版）》2008年第6期73-76,共4页Journal of Huazhong University of Science and Technology(Natural Science Edition)

摘　　要：针对短时平稳序列,设计了一种更有效的基于线性调频Z变换(CZT)的改进Rife频率估计器.该估计器借助关于待估频率的先验知识,首先利用正弦采样序列的CZT谱峰左右谱线的对称性情况确定出真实频率的大致位置,然后类似Rife法作出精确频率估计并分析了其性能.蒙特卡罗模拟实验表明相比基于快速傅里叶变换(FFT)的Rife法,该算法具有更高的抗噪性,全频率范围内估计精度更高、估计均方根差十分接近理论克拉美罗下限(CRLB),抵抗相邻近谱分量的干扰能力更强,且可在更短的数据时长条件下进行高性能频率估计,非常适合于平稳性差、性能要求高的各种多分量参数估计场合.According to the short-time stationary sequence usually sampled in applications, a more effective chirp Z transform（CZT）-based improved Rife-Jane interpolated frequency estimator is presented, which determines the coarse position of actual frequency in the CZT linear spectrum model of single tone by the degree of symmetry of the adjacent left and right line to its CZT peak and then chooses the two reliable lines as the base for the CZT-based Rife-Jane＇s like frequency estimation according to certain priori information about it. Theoretical performance analysis and computer Monte -Carlo simulations show that the algorithm is more robust, outperforms the traditional Rife-Jane＇s estimator in accuracy, the CRLB-approximation RMSE of estimation and discriminating capability for adjacent overlapping. It is also shown that the CZT-based estimator performs well even in the case of very short samples, which is quite suitable for applications of strict stationary, high performance requirement.

关 键 词：频率估计 线性调频Z变换 短时平稳 近邻干扰 Rife-Jane估计 克拉美罗下限 

分 类 号：TN911.6[电子电信—通信与信息系统]