Phase Noise Suppression in OFDM systems in Presence of IQ Imbalance
The implementation of OFDM system suffers from the effect of phase noise and IQ imbalance, which disturb the orthogonality between subcarriers and cause intercarrier interference (ICI). When treated separately, effective algorithms, such as the ICI self-cancellation scheme, exist for suppression of phase noise as well as IQ imbalance. However, with both effects present, such algorithms do not lead to effective suppression. In this paper, we propose a novel technique to jointly combat the IQ imbalance and phase noise at baseband. An IQ imbalance estimation and compensation module, which is robust against phase noise, is added in the ICI self-cancellation based OFDM system. After the IQ imbalance has been compensated in the time domain, the ICI self-cancellation scheme of data-conjugate method is used to suppress the phase noise and the residual IQ imbalance. This scheme has a fast convergence and a nearly optimal BER performance even for large IQ imbalance in AWGN channel. In multipath channel, even for large IQ imbalance, this joint suppression scheme offers frequency diversity gain and as a result, the BER performance surpasses that of the conventional OFDM system without IQ imbalance and phase noise.
Shigang Tang Ke Gong Changyong Pan Zhixing Yang Kewu Peng
The State Key Lab. on Microwave and Digital Communications Department of Electronic Engineering Tsinghua University, Beijing 100084, P. R. China
国际会议
2006 International Conference on Communications,Circuits and Systems(第四届国际通信、电路与系统学术会议)
广西桂林
英文
1184-1188
2006-06-25（万方平台首次上网日期，不代表论文的发表时间）