OFDM系统中一种改进的频偏估计算法

An improved frequency offset estimation algorithm for OFDM system

针对正交频分复用系统中载波频偏降低系统性能的问题,提出了一种改进的频偏估计算法。改进算法使用一个简单的复训练序列,可以有效的在时域中估算小数倍频偏,在频域中估算整数倍频偏。仿真结果显示,改进后的频偏估计算法比Schmidl&Cox算法信噪比损失降低了1.5dB,比P.Moose算法降低了2.5dB。能够有效的提高频偏估计的准确性,且在低复杂度的情况下提供了较大的频偏估计范围。

In orthogonal Frequency Division Multiplexing（OFDM） system, Carrier frequency off sets （CFOs） degrade the estimation algorithm is p quence, and can effectivel system performance significantly. An improved carrier frequency offset re Y sented in this paper. The algorithm uses one complex training se estimate fractional frequency offset in the time domain and the integer frequency offset in the frequency domain. Simulation results show that the signal noise rate （SNR） loss calculated by the improved carrier frequency offset estimation algorithm is reduced 1. 5dB than that by Schmidl algorithm, and 2.5dB by P. Moose algorithm. The improved algorithm can effectively improve the frequency estimation accuracy and provides a wide acquisition range for the carrier frequency offset with low complexity.