Multicell Zero-Forcing and User Scheduling on the Downlink of a Linear Cell Array

Autor:	Bang, H. J., Gesbert, D.
Rok vydání:	2009
Předmět:	Computer Science - Information Theory
Druh dokumentu:	Working Paper
Popis:	Coordinated base station (BS) transmission has attracted much interest for its potential to increase the capacity of wireless networks. Yet at the same time, the achievable sum-rate with single-cell processing (SCP) scales optimally with the number of users under Rayleigh fading conditions. One may therefore ask if the value of BS coordination is limited in the many-user regime from a sum-rate perspective. With this in mind we consider multicell zero-forcing beamforming (ZFBF) on the downlink of a linear cell-array. We first identify the beamforming weights and the optimal scheduling policy under a per-base power constraint. We then compare the number of users m and n required per-cell to achieve the same mean SINR, after optimal scheduling, with SCP and ZFBF respectively. Specifically, we show that the ratio m/n grows logarithmically with n. Finally, we demonstrate that the gain in sum-rate between ZFBF and SCP is significant for all practical values of number of users. Comment: 15 pages, 3 figures
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/0911.0971 Zobrazit plný text záznamu View this record from Arxiv