正交频分复用系统中同步位置估计方法的研究

Study on Method for Estimating Synchronization Position in OFDM System

从正交频分复用(orthogonal frequency division multiplexing,OFDM)技术的角度出发,提出了一种基于循环前缀(cyclic prefix,CP)的OFDM同步位置估计方法[1],旨在接收到CP后能启动同步估计,然后将循环前缀等分为两段信号,比较分段信号的信噪比(signal-noise ratio,SNR),并采用递归二等分的方法得出OFDM有效数据符号的同步起始位置,计算简单,同步速度快。通过仿真论证发现,本文提出的方案较常规方案精确度更高。

In this paper we propose an estimation method of synchronization starting point based on the cyclic prefix from the aspect of orthogonal frequency division multiplexing technology. The purpose of the method is to enable estimation of synchronization immediately after receiving CP, and then CP is devived into two equal-length signals. Synchronization starting point of effective OFDM data signal can be detected by comparing of SNR of these two fragmented signals and by using recursive bisection method. This method has lower computing complexity and higher synchronization speed. Simulation results show that the proposed method can achieve higher precision than conventional methods.