数字接收机I/Q支路不平衡的时域补偿  

Time domain compensation of I/Q imbalance in digital receivers

作　　者：唐世刚[1] 龚克[1] 潘长勇[1] 杨知行 

机构地区：[1]清华大学电子工程系微波与数字通信技术国家重点实验室,北京100084

出　　处：《清华大学学报（自然科学版）》2007年第1期49-52,共4页Journal of Tsinghua University(Science and Technology)

基　　金：国家自然科学基金资助项目(50177001)

摘　　要：为了消除数字接收机同相与正交(I/Q)支路幅度和相位不平衡对数字接收机接收性能的影响,根据时域数据I/Q支路的功率与正交关系,提出了一种I/Q支路不平衡参数估计和补偿方法。该方法的估计和补偿均在时域进行,可以在计算复杂度、估计时间和补偿性能三者之间进行折衷;它无需导频或者训练序列,可应用于多种制式的单载波和多载波接收机中。仿真结果表明:利用该方法的64QAM-OFDM系统误码率在AWGN信道下可以达到理想性能,在多径信道下1×10-3误码率处的性能损失可以减小到0.1 dB左右。The performance degradation of digital receivers caused by I/Q gain and phase imbalances is improved by a method to estimate and compensate for I/Q imbalances based on the power and orthogonality relationships between the in-phase and quadrature channels of the time domain data. Both of the estimates and the compensation are carried out in the time domain which allows for a flexible tradeoff between computational complexity, estimation time and compensation performance. Because the estimation of the I/Q imbalance does not need any pilots or training sequence, this technique is applicable to a wide range of single-carrier and/or multi-carrier communication and broadcasting systems. Simulations of a 64QAM-OFDM system show that this technique can achieve the optimal bit error rate （BER） performance under AWGN channel, and can reduce the performance degradation to about 0. 1 dB when the BER is 10^-3 under frequency-selective fading channel.

关 键 词：数字接收机 I/Q支路不平衡 时域补偿 

分 类 号：TN929.5[电子电信—通信与信息系统]