一种新的正弦波频率估计算法  

Novel frequency estimation method for sinusoidal signal

作　　者：张刚兵[1] 钱显毅[1] 

机构地区：[1]常州工学院电子信息与电气工程学院,江苏常州231002

出　　处：《华中师范大学学报（自然科学版）》2012年第1期40-44,共5页Journal of Central China Normal University：Natural Sciences

基　　金：江苏省高校自然科学基金项目(10KJD480003);常州工学院校级基金项目(YN1101)

摘　　要：研究了高斯白噪声条件下大样本点单一正弦波信号的频率估计方法.首先利用离散傅里叶变换确定频率粗估计,然后以该值为参考频率构造本地信号,将原信号下变频至基带,对基带信号分段求和,能得到一个新的正弦波信号,该信号的频率为真实频率与参考频率之差,最后利用最小二乘法估计新信号的载频,修正粗估计值就能得到原信号频率的最优估计.推导了算法的渐近方差与克拉美-罗限之间的关系.仿真结果表明,本算法能适用于整个频段范围,频率估计的精度接近正弦波频率估计的克拉美-罗限.A novel algorithm for frequency estimation of sinusoid with many samples in the complex white Gaussian noise was proposed.A coarse frequency estimate was obtained through discrete Fourier transform and a sequence was constructed with the coarse frequency estimate being a reference frequency.Then the original sequence was converted into baseband by down-conversion.A new sinusoid was acquired after correlation accumulation,of which the frequency was the difference between the original frequency and reference one.Linear regression made it possible to get the optimal frequency difference estimate.The relationship between the asymptotic error variance（AEV） and the Cramer-Rao lower bound（CRLB） was derived.Simulation results show that the performance of the proposed algorithm approaches the CRLB of the sinusoidal signal when the signal-to-noise ratio（SNR） is higher than the SNR threshold.

关 键 词：大样本 离散傅里叶变换 相关积累 频率估计 

分 类 号：TN911[电子电信—通信与信息系统]