OFDM系统在多径环境下的定时同步算法  

A new timing synchronization method for OFDM systems under the multi-path channels

作　　者：汪园丽[1] 葛建华[1] 王勇[1] 聂远飞[1] 

机构地区：[1]西安电子科技大学综合业务网理论与关键技术国家重点实验室,陕西西安710071

出　　处：《西安电子科技大学学报》2006年第2期316-321,共6页Journal of Xidian University

基　　金：国家自然科学基金重点项目(60332030):移动宽带视频广播传输系统及关键技术研究;国家自然科学基金重大项目(60496316):新型载波系统和智能无线多媒体接入技术

摘　　要：在无线信道中,由于多径的存在,影响了OFDM系统中定时的准确性,就此提出了一种新的基于循环前缀的符号定时同步算法及其改进算法,利用独立的相关块之间值的差异性给出定时同步位置,同时可估计出多径时延及循环前缀的长度.在给出其推导过程的基础上给出了仿真结果,并与现有的一些算法进行了比较,结果表明新算法估计精度较高且易于实现.In wireless environment, the accuracy of timing synchronization in an OFDM system would be affected by multi-path. For the sake of solving this problem, a new method and its improved one based on the cyclic prefix are proposed in this paper, which uses the separate block of the correlation between the cyclic prefix and its duplicated part which is different from the continuous correlation or point correlation in the existing methods. The proposed methods could obtain the time delay and the length of the cyclic prefix, with their deviation and simulation given. It is shown that the proposed methods have higher precision and lower complexity compared with the existing methods. Also, they could obtain the time delay of the channel and the length of the cyclic prefix.

关 键 词：OFDM(正交频分复用) 定时同步 循环前缀 多径 

分 类 号：TN913[电子电信—通信与信息系统]