An upper bound for limited rate feedback MIMO capacity
IEEE Transactions on Wireless Communications
Robust precoder adaptation for MIMO links with noisy limited feedback
IEEE Transactions on Information Theory
Outage behavior of discrete memoryless channels under channel estimation errors
IEEE Transactions on Information Theory
Performance analysis of RVQ-based limited feedback beamforming codebooks
ISIT'09 Proceedings of the 2009 IEEE international conference on Symposium on Information Theory - Volume 4
Limited feedback for multi-carrier beamforming: a rate-distortion approach
ISIT'09 Proceedings of the 2009 IEEE international conference on Symposium on Information Theory - Volume 1
Distributed beamforming with limited feedback in regenerative cooperative networks
WiCOM'09 Proceedings of the 5th International Conference on Wireless communications, networking and mobile computing
Multiuser MIMO achievable rates with downlink training and channel state
IEEE Transactions on Information Theory
Comparison of practical feedback algorithms for multiuser MIMO
IEEE Transactions on Communications
Optimization of training and feedback overhead for beamforming over block fading channels
IEEE Transactions on Information Theory
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Multiple-input-multiple-output (MIMO) communication systems can provide large capacity gains over traditional single-input-single-output (SISO) systems and are expected to be a core technology of next generation wireless systems. Often, these capacity gains are achievable only with some form of adaptive transmission. In this paper, we study the capacity loss (defined as the rate loss in bits/s/Hz) of the MIMO wireless system when the covariance matrix of the transmitted signal vector is designed using a low rate feedback channel. For the MIMO channel, we find a bound on the ergodic capacity loss when random codebooks, generated from the uniform distribution on the complex unit sphere, are used to convey the second order statistics of the transmitted signal from the receiver to the transmitter. In this case, we find a closed-form expression for the ergodic capacity loss as a function of the number of bits fed back at each channel realization. These results show that the capacity loss decreases at least as O(2-B(2MMt-2)/) where B is the number of feedback bits, Mt is the number of transmit antennas, and M=min{Mr,Mt} where Mr is the number of receive antennas. In the high SNR regime, we present a new bound on the capacity loss that is tighter than the previously derived bound and show that the capacity loss decreases exponentially as a function of the number of feedback bits.