空频码异步协作通信中的多CFO补偿  

Multiple carrier frequency offset compensation in space-frequency code cooperative communications system

作　　者：朱冰莲[1] 张松[1] 刘海丰[1] 杨晓芳[1] 

机构地区：[1]重庆大学通信工程学院,重庆400044

出　　处：《计算机工程与应用》2011年第18期149-152,共4页Computer Engineering and Applications

基　　金：国家自然科学基金(No.60872038);重庆大学"211工程"三期创新人才培养计划建设项目(No.S-09102)~~

摘　　要：在协作通信中为了对抗同步误差,可基于OFDM技术在中继节点采用空频码实现协作分集和多径分集。OFDM可以抗定时误差,但对载波频率偏移非常敏感,对于协作通信,多个载波频率偏移的存在使得频率补偿很难实现。利用空频码结构和载波间干扰能量分布特点,提出在发射端调整空频码相对位置,在接收端进行多次频率搬移和相应的FFT变换,能有效对抗多个载波频率偏移。在此基础上采用Q抽头滤波算法,以较低的算法复杂度实现了接近于最小均方误差的性能。To combat synchronization errors in cooperative communication,Orthogomal Frequence Digital Multiplexing（OFDM） technique is applied to achieve the full cooperative diversity and full multipath diversity for asynchronous cooperative com- munications,in which a kind of Space-Frequency（SF） code is used at relay nodes.Although OFDM can combat timing errors,it is very sensitive to Carrier Frequency Offset（CFO）.For cooperative communication,multiple CFO makes frequency compensation difficult if not impossible.By exploiting the structure of the SF code and energy distribution characteristics of Inter-Carrier Interference（ICI）,this paper proposes re-ranging the SF code at transmitter and multiple frequency shifts with corresponding FFT at receiver to combat multiple CFO effectively.Based on this,by using Q tap method,it gets a perfor- mance to close Minimum Mean Square Erro（rMMSE）at the cost of lower algorithm complexity.

关 键 词：协作通信 空频码 载波频率偏移 正交频分复用技术 

分 类 号：TN929.5[电子电信—通信与信息系统]