【摘要】 提出了一种改进的适用于车速无线信道的OFDM联合同步算法。该算法首先利用一组特殊的时域正交PN序列进行联合定时同步和大频偏估计,并从理论上分析了大频偏估计之后的残留频偏范围;之后使用多个重复的短训练符号完成残留频偏估计。理论分析和仿真结果表明,改进的算法不但能解决无线信道下第一径不是最强径时的定时同步问题,而且在可能出现多个等功率路径的车速无线信道下具有更高的频偏捕获概率和更好的频偏估计性能。更多还原

【Abstract】 A joint synchronization algorithm for OFDM system in vehicular wireless channel was proposed.In the proposed algorithm,a special orthogonal PN sequence was used first to realize timing synchronization and large frequency offset estimation,and the scale of residual frequency offset was analyzed.Then a group of repetitive short training sequence was used to finish the residual frequency offset estimation.Theory analysis and simulation results show that the improved algorithm can not only solve the problem of timing estimation when the first path is not the strongest path in wireless channel,but can also improve the acquisition probability and the estimation accuracy of frequency offset in vehicular wireless channel,where equal power paths may occur.更多还原