改变窗长相位差校正法的改进与抗噪性能分析  

Improvement and Anti-Noise Performance Analysis of Window-Length Changing Phase Difference Correction

作　　者：丁康[1] 杨志坚[1] 

机构地区：[1]华南理工大学汽车工程学院,广东广州510640

出　　处：《华南理工大学学报（自然科学版）》2007年第10期210-213,共4页Journal of South China University of Technology(Natural Science Edition)

基　　金：国家自然科学基金资助项目(50475095)

摘　　要：提出了一种改进的改变窗长相位差校正法来估计谐波信号的频率,与原方法相比,改进后的方法只需做一次快速傅立叶变换(FFT)和一次单点离散傅立叶变换(DFT),提高了运算速度.分析了改进方法的抗噪声性能,推导出了在高斯白噪声背景下频率估计误差的方差公式,并通过仿真计算验证了推导公式的正确性.仿真结果表明改进后的方法具有更强的抗噪能力.This paper presents a method of improved winodw-length changing phase difference correction to estimate the frequency of harmonic signal. As compared with the unimproved one, the proposed method only needs to perform one fast Fourier transelation （FFT） and one single-point discrete Fourier translation （DFT）. Thus, the processing speed is greatly increased. The anti-noise performance of the improved method is also investigated in this paper, and the variance equation of the frequency estimation error in the presence of Gaussian white noise is then deduced. Simulation is finally performed to verify the correctness of the variance equation. The results reveal the good anti-noise capability of the improved method.

关 键 词：频率估计 相位差 抗噪 频谱分析 校正 

分 类 号：TN911.7[电子电信—通信与信息系统] TN911.4[电子电信—信息与通信工程]