一种低复杂度基于公平性的MIMO-OFDMA资源分配方案

A Low Complexity Resource Allocation Scheme with Proportional Fairness for MIMO-OFDMA System

该文针对MIMO-OFDMA下行链路系统,考虑在总功率和BER以及用户数据速率成比例的约束下,以获取整个系统吞吐量极大化为准则,提出一种基于成比例公平性约束的资源分配方案。新的方案基于MIMO信道状态信息,利用特征子信道来确定子载波和功率分配,充分利用了空间域,频域以及多用户分集提高系统的频谱效率。在子载波分配时,松弛成比例约束条件,使用户数据速率近似地成比例于每个用户分配的子载波数,推导出一种线性的不需要迭代的低复杂度的功率分配方案。仿真和分析表明,整个方案在保证系统吞吐量的前提下,取得了用户间良好的速率公平性,同时又具有较低的计算复杂度。

This paper presents a new scheme based on proportional fairness for MIMO-OFDM downlink resource allocation to maximize the sum of user data rates,subject to constraints on total power,bit error rate,and proportionality among user data rates. This new scheme embraces the ability to simultaneously exploit space,frequency and multi-user diversity to improve spectrum efficiency. 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. A linear non-iterative power allocation method with low complexity is deduced that is made by the relaxation of strict user rate proportionality constraints. Simulation results show that this new adaptive allocation scheme can achieve good tradeoff between capacity and fairness,while requiring significantly less computation.