基于循环前缀的OFDM系统频偏自适应跟踪算法

Adaptive frequency offset tracking algorithm for OFDM based on cyclic prefix

为了减小正交频分复用系统受频率偏差的影响,本文提出了基于循环前缀的频偏自适应跟踪算法,该算法利用循环前缀,对载波频偏进行跟踪。文中用最陡下降法和变步长自适应算法进行了计算机仿真,给出了频偏跟踪曲线和BPSK的星座图。理论分析和仿真结果表明,本文提出的方法运算复杂度低,并具有较好的收敛性,能够改善解调性能。

To reduce the impact of carrier frequency offset in OFDM system, we propose a new adaptive frequency offset tracking algorithm based on cyclic prefix in this paper. This algorithm uses cyclic prefix to estimate and track frequency offset. Steepest descent algorithm and variable step size adaptive algorithm designed by us are used in computer simulations. The tracking curve, MSE, and constellation of BPSK are presented. Theoretical analysis and computer simulations confirm that the algorithm has low complexity and fast convergence. The algorithm improves the demodulation performance of OFDM system.