Distributed resource optimization for multi-user indoor power line communications

Abstract

In this paper, we study the resource optimization for multi-user orthogonal frequency division multiple access (OFDMA)-based broadband power line communication (PLC) system. In order to reduce the signalling overhead and enhance the network scalability, we focus on designing the distributed resource optimization strategy. Firstly, we formulate the PLC resource optimization as a network utility maximization problem. For solving the formulated problem, a two-step decomposition method is developed to decompose the formulated problem into a power control subproblem and a network configuration (subchannel allocation) subproblem. Then, we develop a continuity relaxation method for solving the optimal solution of the power control subproblem. In order to overcome the difficulty of combinatorial nature of subchannel allocation subproblem, we propose a Markov approximation framework to obtain the near-optimal solution. Finally, a distributed joint subchannel allocation and power control algorithm is proposed for optimizing the PLC system energy efficiency. Simulation results validate the theoretical analysis of our proposed scheme.