Publica
Hier finden Sie wissenschaftliche Publikationen aus den FraunhoferInstituten. Resource allocation in multiantenna systems  Achieving maxmin fairness by optimizing a sum of inverse SIR
 IEEE transactions on signal processing 54 (2006), No.6, Pt.1, pp.19901997 ISSN: 00963518 ISSN: 00189278 ISSN: 00961620 ISSN: 1053587X 

 English 
 Journal Article 
 Fraunhofer HHI () 
Abstract
We address the problem of jointly optimizing transmit powers and linear preequalizers (e.g., beamformers) for a multiuser downlink channel. All results can be transferred to the dual uplink channel. The link quality of each user is determined by the signaltointerference ratio (SIR). Two common strategies for distributing the system resources by joint optimization of transmit powers and beamformers are 1) maximize the minimum SIR, to which we refer as maxmin fairness, and 2) minimize the sum of weighted inverse SIR. Both strategies are generally not equivalent. In this paper, it is shown how the weighting factors should be chosen so that the sum optimization approach achieves optimal maxmin fairness. An efficient iterative algorithm is proposed for solving this nonlinear optimization problem. Monotonicity and convergence are proved.