TY - GEN

T1 - Sum-rate of MIMO broadcast channels with one bit feedback

AU - Diaz, Jordi

AU - Simeone, Osvaldo

AU - Bar-Ness, Yeheskel

PY - 2006/12/1

Y1 - 2006/12/1

N2 - The sum-capacity of a multi-antenna broadcast Gaussian channel is known to be achieved by Dirty Paper Coding techniques, or, asymptotically in the number of users n, by beamforming methods, that require full channel state information at the base station. Based on the opportunistic beamforming principle, it has been recently shown that the optimal scaling law of the sum-rate with respect to n, for fixed signal to noise ratio and number of transmitting antennas M, (i.e., M log log n) can be achieved by employing a feedback of only one real and one integer number per user. Moreover, it was proved that a linear scaling with respect of M can be guaranteed only if M scales no faster than logrt. In this paper, the optimal scaling law of the sum-rate with respect to n is proved to be achievable with only one bit of feedback per user. The proof builds on opportunistic beamforming and binary quantization of the signal to noise plus interference ratio. Moreover, the linear scaling of the sum-rate with M is demonstrated to hold for M growing no faster than logrt even with such a reduced feedback. Finally, the results above are extended to the MIMO case, where each user is equipped with multiple antennas.

AB - The sum-capacity of a multi-antenna broadcast Gaussian channel is known to be achieved by Dirty Paper Coding techniques, or, asymptotically in the number of users n, by beamforming methods, that require full channel state information at the base station. Based on the opportunistic beamforming principle, it has been recently shown that the optimal scaling law of the sum-rate with respect to n, for fixed signal to noise ratio and number of transmitting antennas M, (i.e., M log log n) can be achieved by employing a feedback of only one real and one integer number per user. Moreover, it was proved that a linear scaling with respect of M can be guaranteed only if M scales no faster than logrt. In this paper, the optimal scaling law of the sum-rate with respect to n is proved to be achievable with only one bit of feedback per user. The proof builds on opportunistic beamforming and binary quantization of the signal to noise plus interference ratio. Moreover, the linear scaling of the sum-rate with M is demonstrated to hold for M growing no faster than logrt even with such a reduced feedback. Finally, the results above are extended to the MIMO case, where each user is equipped with multiple antennas.

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U2 - 10.1109/ISIT.2006.261820

DO - 10.1109/ISIT.2006.261820

M3 - Conference contribution

AN - SCOPUS:38549108061

SN - 1424405041

SN - 9781424405046

T3 - IEEE International Symposium on Information Theory - Proceedings

SP - 1944

EP - 1948

BT - Proceedings - 2006 IEEE International Symposium on Information Theory, ISIT 2006

T2 - 2006 IEEE International Symposium on Information Theory, ISIT 2006

Y2 - 9 July 2006 through 14 July 2006

ER -