改进的OFDM系统下行链路符号定时同步算法  

Improved symbol timing synchronization algorithm for OFDM system in downlink

作　　者：孙珺[1] 刘明骞[1] 李兵兵[1] 黄子甲[1] 李艳玲[1] 

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

出　　处：《西北大学学报（自然科学版）》2012年第5期739-743,共5页Journal of Northwest University（Natural Science Edition）

基　　金：国家科技重大专项基金资助项目(2009ZX03003-003-01);国家自然科学基金资助项目(61271299);国家"863"高技术研究发展计划基金资助项目(2007AA01Z288);高等学校学科创新引智计划基金资助项目(B08038)

摘　　要：目的解决传统的正交频分复用(OFDM)系统符号定时同步算法抗多径衰落性能不足的问题。方法首先利用已知的前导序列和前导的倒序列作为训练序列,然后将输入序列、训练序列和倒训练序列进行乘积形成新的序列,最后将输入序列与此新的序列进行互相关运算。结果该方法在高斯信道和多径信道下都具有较好的定时同步性能。结论该方法有效地提高了定时精度,降低了对多普勒频移的敏感程度。Aim To cope with the deficiency of the anti-muhipath fading capability in the traditional symbol timing synchronization algorithm for Orthogonal Frequency Division Multiplexing （0FDM） system. Methods Firstly, the known leader sequence and its inverse sequence were used as the training sequence. And then a new sequence was formed by the product of the input sequence, the training sequence and the inverse training sequence. Finally, the cross-correlation operation for the input sequence and the new sequence was carried out. Results The proposed al- gorithm has better symbol timing synchronization performance in AWGN channel and muhipath fading channel. Conclusion The proposed algorithm has greatly decreased the sensitive degree with doppler shift and improved the symbol timing synchronization performance.

关 键 词：符号定时同步 正交频分复用(OFDM) 训练序列 共轭对称 

分 类 号：TN911.7[电子电信—通信与信息系统]