摘要: 基于自相关函数的载波频偏估计算法存在捕获范围与估计精度相矛盾的问题。针对该问题,采取新的相位展开措施,对观测信号自相关函数做快速傅里叶变换以粗估频偏,利用该频偏对高延时自相关函数值进行相位展开,对频偏估计结果求均值。该算法在保持较高估计精度的同时将估计范围扩大到1/2MT。仿真实验结果证明了该算法的有效性。
关键词:
载波恢复,
频偏估计,
自相关函数,
快速傅里叶变换,
相位展开
Abstract: Capturing-range and estimation accuracy of autocorrelation-based carrier frequency offset estimator is a pair of contradictions. Aiming at this problem, a novel phase unwrapping algorithm is proposed. Coarse frequency offset is obtained based on Fast Fourier Transform(FFT) of autocorrelation function of observation signal, and the phase of long delay autocorrelation function value is unwrapped by the coarse frequency offset, three estimation results are averaged. With high estimation accuracy, the novel estimator’s capturing-range can be extended to 1/(2MT). Simulation experimental results verify the effectiveness of the proposed algorithm.
Key words:
carrier recovery,
frequency offset estimation,
autocorrelation function,
Fast Fourier Transform(FFT),
phase unwrapping
中图分类号:
王品, 黄焱, 王超, 杨华. 基于自相关的宽范围高精度频偏估计算法[J]. 计算机工程, 2011, 37(4): 102-103.
WANG Pin, HUANG Yan, WANG Chao, YANG Hua. Autocorrelation-based Frequency Offset Estimation Algorithm with Wide Range and High Accuracy[J]. Computer Engineering, 2011, 37(4): 102-103.