重庆大学学报：自然科学版2012，Vol.35Issue(4)：123-127,5.
利用空载波的OFDM系统的IQ误差盲估计方法
Blind estimation of IQ imbalance with null subcarriers for OFDM systems
摘要
Abstract
Orthogonal frequency division multiplexing （OFDM） is sensitive to the in-phase and quadraturephase （IQ） imbalance induced by the direct conversion architectures. A compensation scheme of IQ imbalance exploiting null subcarriers in OFDM symbols is presented. The proposed algorithm is with high bandwidth utilization because the training symbols are not required. The effect of IQ imbalance on OFDM systems is studied, and the mirror relationship between the FFT of a sequence and that of its conjugate is employed to estimate and compensate the IQ imbalance. This method can be applied to multiple input multiple output （MIMO） OFDM systems with space time block code （STBC）. Performance analysis shows that the proposed algorithm is asymptotically unbiased. The variance is inversely proportional to the number of OFDM symbols, null subcarriers, the SNR and the channel frequency response, and proportional to the IQ imbalance. Simulation results demonstrate that this scheme can obtain almost the optimal bit error rate （BER）.关键词
正交频分复用/空载波/IQ误差/多输入多输出Key words
orthogonal frequency division multiplex/null subcarriers/IQ imbalance/multiple inputmultiple output分类
信息技术与安全科学引用本文复制引用
许炜阳,吴皓威..利用空载波的OFDM系统的IQ误差盲估计方法[J].重庆大学学报：自然科学版,2012,35(4):123-127,5.基金项目
中央高校基本科研费资助项目 （）
重庆市自然科学基金资助项目 （）
