OFDM系统发射机/接收机IQ不平衡的无反馈时域补偿

摘要

To resolve the problems of time delay and system overhead in conventional time-domain IQ (in-phase and quadrature-phase ) imbalance compensation algorithms for orthogonal frequency division multiplexing ( OFDM ) systems , a time-domain algorithm for IQ imbalance compensation without feedback was proposed.The algorithm can realize the joint compensation of transmitter/receiver (Tx/Rx) IQ imbalance at the receiver.Special training sequences were also designed for joint estimation of IQ imbalance parameters and channels.The simulation results showed that the proposed algorithm could achieve good system performance with only two training symbols per frame.Thus it is an effective IQ imbalance compensation algorithm without feedback for OFDM systems.%针对OFDM系统传统的同相、正交支路(IQ)不平衡的时域补偿算法所存在的时延及系统开销问题,提出了一种无反馈的IQ不平衡时域补偿算法,该算法可在接收端对发射机和接收机分别产生的IQ不平衡进行联合补偿.同时设计了特殊结构的训练序列,以实现信道和IQ不平衡参数的联合估计.仿真表明,该算法仅需两个正交频分复用(OFDM)训练符号即可达到较好的系统误码性能,因此是一种高效且无需反馈的OFDM系统发射机/接收机的IQ不平衡补偿算法.