无线OFDM系统时频同步方法研究

Timing and frequency synchronization method for wireless OFDM systems

在分析OFDM系统同步训练符号性质的基础上,设计出一个具有伪随机序列加权因子的新同步训练符号,并提出基于该训练符号的同步方法.利用新训练符号中的伪随机序列加权因子和数据序列的相关特性进行符号同步偏移估计;在符号同步的基础上,利用消去新训练符号中伪随机加权因子的数据序列进行频偏估计.仿真结果表明所提方法的符号同步偏移估计精度和频偏估计范围均优于已有的同步方法.

Based on the analysis of the synchronization training symbols in orthogonal frequency division multiplexing （OFDM） systems, a new training symbol weighted by the pseudo-noise （PN） sequence is designed, and the corresponding synchronization method is proposed. In the proposed method, the correlation properties of the PN weighted factor and the training symbol are utilized in the timing offset estimation. Based on the timing synchronization, the PN weighted factor in the training symbol is removed, and the renewed training symbol is used to estimate the frequency offset. Simulation results show that the accuracy of timing synchronization and the estimate range of the frequencv offset outperform those of the other available methods.