A Novel Adaptive Resource Allocation Scheme in Downlink OFDMA-Based System

Orthogonal frequency division multiple access (OFDMA) has been selected as multiple access technology by future wireless communication systems, such as Long Term Evolution (LTE), International Mobile Telecommunications-Advanced (IMT-Advanced), etc.. Resource allocation is a crucial issue in OFDMA-based system. The existing algorithms are mainly concentrated on two basic modes, "adjacent" mode and "distributed" mode, to build a resource unit (RU) composed of a set of subcarriers. In this paper, we propose a novel adaptive resource allocation scheme to realize flexible and efficient subcarriers distribution. A novel mode of building a RU in OFDMA-based system is introduced. The adaptive time-frequency scheduling algorithm based on the novel mode is explained in details. Simulation results show that the proposed scheme could achieve a better balance of fairness and throughput compared to the conventional resource allocation schemes based on "adjacent" mode and "distributed" mode.