一种新的OFDM系统多符号联合差分时间同步算法  

A novel symbol synchronization scheme using multiple symbols in OFDM systems

作　　者：郭达[1] 江峰[1] 宋梅[1] 宋俊德[1] 

机构地区：[1]北京邮电大学电子工程学院,北京100876

出　　处：《电路与系统学报》2007年第3期94-97,共4页Journal of Circuits and Systems

基　　金：国家"863计划项目"(2003AA12331004)

摘　　要：本文提出了一种OFDM系统多符号联合差分时间同步算法。首先用接收到的时域OFDM信号进行间隔为符号长度加循环前缀(Cycle Prefix,CP)长度的自相关得到相关信号。然后使用相干信号中相隔符号长度的两个采样的差别来得到时间信息。使用这种算法,CP中不受ISI影响的区域的终点可以准确的识别出来。仿真结果证明该算法克服了现有算法的某些缺陷,性能有所改进。Time synchronization is essential to OFDM transfer system. A symbol synchronization method for OFDM system is proposed. According to this method, the correlation signal is generated by taking the conjugate product of the sample with another sample the symbol and cyclic-prefix （CP） length positions apart. Then the difference between two of the correlation signal samples is used to extract timing information, where the difference of the two samples＇ position is one symbol length. Using this method, end points of ISI free region can be identified comparative exactly. The simulation shows that the proposed method overcomes some disadvantages of the earlier methods.

关 键 词：正交频分复用 时间同步 循环前缀 多径衰落信道 

分 类 号：TN919.5[电子电信—通信与信息系统]