Power Control for Sum-Rate Maximization on Interference Channels Under Sum Power Constraint

Abstract

In this paper, we consider the problem of power control for sum-rate maximization on multiple interfering links [transmitter-receiver pairs (Tx-RX)] under a sum power constraint. We consider a single-frequency network, where all pairs are operating in the same frequency band, thereby creating interference with each other. We study the power-allocation problem for sum-rate maximization with and without quality-of-service (QoS) requirements on individual links. When the objective is only sum-rate maximization without QoS guarantees, we develop an analytic solution to decide optimal power allocation for a two-TX-RX-pair problem. We also develop a low-complexity iterative algorithm for a three-TX-RX-pair problem. For a generic N > 3 TX-RX pair problem, we develop two low-complexity suboptimal power-allocation algorithms. The first algorithm is based on the idea of making clusters of two or three TX-RX pairs and then leveraging the power-allocation results obtained for the twoand three-TX-RX-pair problems. The second algorithm is developed by using a high signal-to-interference-plus-noise ratio (SINR) approximation, and this algorithm can be also implemented in a distributed manner by individual TXs. We then consider the same problem but with additional QoS guarantees for individual links. We again develop an analytic solution for the two-TX-RX-pair problem and a distributed algorithm for N > 2 TX-RX pairs.