Achievable Throughput Optimization in OFDM Systems in the Presence of Interference and its Application to Power Line Networks

The aim of this paper is to study the bit-loading and power allocation problem in the presence of interference (Inter-carrier Interference (ICI) and Inter-Symbol Interference (ISI)) in Orthogonal Frequency Division Multiplexing (OFDM) systems. ISI and ICI significantly degrade the performance of OFDM systems and make the resource management optimized without the assumption of interference less efficient. To solve this problem, an initial solution based on the greedy approach is proposed in this paper. Then, several reduced complexity approaches, which yield a little degradation compared to the initial solution, have been developed. Simulation results presented in the context of Power Line Communication (PLC) show that the performance of proposed algorithms is tight with their upper bound. Moreover, these algorithms efficiently improve the system performance as compared to the constant power water-filling allocation algorithm as well as maximum power allocation algorithm.

I. Introduction

IN the past decades, the use of PLC systems for high rate indoor broadband communications has spread rapidly. Since PLC doesn't require any new wire installation, it is economically attractive for indoor local area network (LAN). It can also be complementary with wireless LAN [1], [2].