TY - JOUR
T1 - Cooperative multicell zero-forcing beamforming in cellular downlink channels
AU - Somekh, Oren
AU - Simeone, Osvaldo
AU - Bar-Ness, Yeshekel
AU - Haimovich, Alexander M.
AU - Shamai, Shlomo
N1 - Funding Information:
Manuscript received January 23, 2007; revised March 04, 2009. Current version published June 24, 2009. This work was supported by a Marie Curie Outgoing International Fellowship and the NEWCOM++ network of excellence both within the 6th and 7th European Community Framework Programmes, by the U.S. National Science Foundation under Grants ANI-03-38807 and CNS-06-25637, the REMON consortium for wireless communication, and the Israeli Science Foundation (ISF). The material in this paper was presented in part at GLOBECOM 2006, San Francisco, CA, November 2006.
PY - 2009
Y1 - 2009
N2 - In this work, a multicell cooperative zero-forcing beamforming (ZFBF) scheme combined with a simple user selection procedure is considered for the Wyner cellular downlink channel. The approach is to transmit to the user with the "best" local channel in each cell. The performance of this suboptimal scheme is investigated in terms of the conventional sum-rate scaling law and the sum-rate offset for an increasing number of users per cell. We term this characterization of the sum-rate for large number of users as high-load regime characterization, and point out the similarity of this approach to the standard affine approximation used in the high-signal-to-noise ratio (SNR) regime. It is shown that, under an overall power constraint, the suboptimal cooperative multicell ZFBF scheme achieves the same sum-rate growth rate and slightly degraded offset law, when compared to an optimal scheme deploying joint multicell dirty-paper coding (DPC), asymptotically with the number of users per cell. Moreover, the overall power constraint is shown to ensure in probability, equal per-cell power constraints when the number of users per-cell increases.
AB - In this work, a multicell cooperative zero-forcing beamforming (ZFBF) scheme combined with a simple user selection procedure is considered for the Wyner cellular downlink channel. The approach is to transmit to the user with the "best" local channel in each cell. The performance of this suboptimal scheme is investigated in terms of the conventional sum-rate scaling law and the sum-rate offset for an increasing number of users per cell. We term this characterization of the sum-rate for large number of users as high-load regime characterization, and point out the similarity of this approach to the standard affine approximation used in the high-signal-to-noise ratio (SNR) regime. It is shown that, under an overall power constraint, the suboptimal cooperative multicell ZFBF scheme achieves the same sum-rate growth rate and slightly degraded offset law, when compared to an optimal scheme deploying joint multicell dirty-paper coding (DPC), asymptotically with the number of users per cell. Moreover, the overall power constraint is shown to ensure in probability, equal per-cell power constraints when the number of users per-cell increases.
KW - Broadcast channel
KW - Distributed antenna array
KW - Fading channels
KW - Scaling law
KW - Sum-rate capacity
KW - Wyner cellular downlink
KW - Zero-forcing beamforming (ZFBF)
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U2 - 10.1109/TIT.2009.2021371
DO - 10.1109/TIT.2009.2021371
M3 - Article
AN - SCOPUS:67650138179
SN - 0018-9448
VL - 55
SP - 3206
EP - 3219
JO - IEEE Transactions on Information Theory
JF - IEEE Transactions on Information Theory
IS - 7
ER -