正交频分复用系统发射机接收机同相/正交不平衡补偿算法  

Tx/Rx IQ Imbalance Compensation Scheme for OFDM Systems

作　　者：梁彦[1] 束锋[1,2] 史夏洁[1] 

机构地区：[1]南京理工大学电子工程与光电技术学院,江苏南京210094 [2]东南大学移动通信国家重点实验室,江苏南京210096

出　　处：《南京理工大学学报》2012年第3期465-469,共5页Journal of Nanjing University of Science and Technology

基　　金：东南大学移动通信国家重点实验室开放研究基金(2010D13)

摘　　要：为了弥补由同相/正交(IQ)不平衡造成的正交频分复用(OFDM)系统误码性能损耗,该文提出了一种发射机和接收机IQ不平衡的频域补偿算法。通过设计特殊结构的训练序列实现了信道和IQ不平衡参数的联合估计。充分挖掘了受IQ不平衡影响的时域多径信道特性,以减少所需训练序列数目。通过利用估计结果对IQ不平衡进行补偿获得OFDM信号检测结果。仿真结果表明,该算法只采用2个OFDM训练符号,其误码性能可超过采用32个训练符号的传统算法,并接近已知IQ不平衡参数和信道信息的理想系统。To mitigate the error performance degradation of orthogonal frequency division multiplexing （OFDM） system caused by in-phase and quadrature-phase （IQ）imbalances, a novel frequency- domain compensation scheme for both transmitter and receiver IQ imbalance is proposed. The channel and IQ imbalance parameters are jointly estimated by designing special training sequences. The number of required training symbols is reduced by fully exploring the time-domain characteristics of muhipath channels affected by IQ imbalance. The OFDM signal detection result is obtained by IQ imbalance compensation using the estimation results. Simulation results show that the error performance of the scheme with two training symbols per frame is better than the traditional scheme with 32 training symbols per frame, and accesses the ideal system with known IQ imbalance parameters and channel knowledge.

关 键 词：正交频分复用 同相/正交 发射机 接收机 不平衡 频域补偿 

分 类 号：TN929.5[电子电信—通信与信息系统]