An enhanced capacity and fairness scheme for MIMO-OFDMA downlink resource allocation

Abstract

This paper presents a new scheme for MIMO-OFDMA (Multiple Input Multiple Output-Orthogonal Frequency Division Multiple Access) downlink resource allocation. This scheme intends to simultaneously enhance capacity and proportional rate fairness among users. A suboptimal power allocation method is also described in detail in this paper. The system objective is to maximize the total capacity subject to constraints on total available power, BER and rate proportions. Based on MIMO channel state information, eigen-channels are intelligently used to determine subcarrier allocation and power allocation, which forms the foundation of the new scheme. Simulation results show that this new adaptive allocation scheme can achieve good tradeoff between capacity and fairness as well as provide much better capacity gain than the conventional static FDMA allocation method. © 2007 IEEE.