Analysis and compensation of I/Q imbalance in MIMO transmit-receive diversity systems

Qi, J. and Aissa, S. (2010) Analysis and compensation of I/Q imbalance in MIMO transmit-receive diversity systems. IEEE Transactions on Communications, 58 (5). pp. 1546-1556. ISSN 0090-6778 doi: 10.1109/TCOMM.2010.05.090225

Abstract/Summary

In wireless communication systems, all in-phase and quadrature-phase (I/Q) signal processing receivers face the problem of I/Q imbalance. In this paper, we investigate the effect of I/Q imbalance on the performance of multiple-input multiple-output (MIMO) maximal ratio combining (MRC) systems that perform the combining at the radio frequency (RF) level, thereby requiring only one RF chain. In order to perform the MIMO MRC, we propose a channel estimation algorithm that accounts for the I/Q imbalance. Moreover, a compensation algorithm for the I/Q imbalance in MIMO MRC systems is proposed, which first employs the least-squares (LS) rule to estimate the coefficients of the channel gain matrix, beamforming and combining weight vectors, and parameters of I/Q imbalance jointly, and then makes use of the received signal together with its conjugation to detect the transmitted signal. The performance of the MIMO MRC system under study is evaluated in terms of average symbol error probability (SEP), outage probability and ergodic capacity, which are derived considering transmission over Rayleigh fading channels. Numerical results are provided and show that the proposed compensation algorithm can efficiently mitigate the effect of I/Q imbalance.

Item Type	Article
URI	https://reading-clone.eprints-hosting.org/id/eprint/33438
Item Type	Article
Refereed	Yes
Divisions	Science
Uncontrolled Keywords	I/Q imbalance; MIMO MRC systems; MIMO transmit-receive diversity systems; Rayleigh fading channels; beamforming; channel estimation; compensation algorithm; in-phase and quadrature-phase; maximal ratio combining; multiple-input multiple-output; signal processing receivers; symbol error probability; wireless communication systems; Multiple-input multiple-output (MIMO); maximal ratio combining (MRC); in-phase and quadrature-phase (I/Q) imbalance; channel estimation; compensation
Publisher	IEEE
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