Distributed Multiple Target-SINRs Tracking Power Control in Wireless Multirate Data Networks

Abstract

In the well-known distributed target-SINR-tracking power control algorithm (TPC), when the system is infeasible, some users transmit at the maximum power without obtaining their target-SINRs. This imposes extra interference on other users and results in an increased number of non-supported users. Several ideas have been proposed to alleviate this deficiency, most of which employ a removal scheme for users who cannot attain their target-SINRs. In this paper, we propose a distributed multiple target-SINRs tracking power control algorithm (MTPC) in which instead of a single target-SINR (as is the case in existing target-SINR tracking schemes), depending on the channel condition, each user dynamically selects its target-SINR from a set of predefined desired target-SINRs. If a user cannot attain a target-SINR, instead of stopping transmission, it may keep transmitting with a lower target-SINR (and hence, lower data rate). We show that our proposed power update function has at least one fixed-point and all of its fixed-points are Pareto and energy efficient, i.e., at the equilibrium, any unilateral increase in the target-SINR of a user leads to a degradation in the target-SINR of at least one other user (i.e., Pareto-efficiency) and furthermore the transmit power vector corresponds to the minimum aggregate power needed for attaining the equilibrium target-SINR vector (i.e., energy efficiency).