Power control algorithms for CDMA networks based on large system analysis

Stefano Buzzi; H. Vincent Poor

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arXiv · 0704.2375

Power control algorithms for CDMA networks based on large system analysis

Stefano Buzzi·H. Vincent Poor

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Abstract

Power control is a fundamental task accomplished in any wireless cellular network; its aim is to set the transmit power of any mobile terminal, so that each user is able to achieve its own target SINR. While conventional power control algorithms require knowledge of a number of parameters of the signal of interest and of the multiaccess interference, in this paper it is shown that in a large CDMA system much of this information can be dispensed with, and effective distributed power control algorithms may be implemented with very little information on the user of interest. An uplink CDMA system subject to flat fading is considered with a focus on the cases in which a linear MMSE receiver and a non-linear MMSE serial interference cancellation receiver are adopted; for the latter case new formulas are also given for the system SINR in the large system asymptote. Experimental results show an excellent agreement between the performance and the power profile of the proposed distributed algorithms and that of conventional ones that require much greater prior knowledge.

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Stefano Buzzi, H. Vincent Poor. 2007-04-18. Power control algorithms for CDMA networks based on large system analysis. https://arxiv.org/abs/0704.2375

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