比例速率约束下基于遗传策略的多用户OFDM系统资源自适应分配算法

基于遗传策略提出了载波和功率自适应分配算法,它在最大化多用户OFDM系统下行链路总容量的同时维持用户之间的比例公平性,是一种将子载波分配和功率分配独立开的低复杂度次优算法。当总功率在载波间均等分布时,首先进行子载波的分配。随后引入遗传算法通过全局搜索实现用户间的功率分配,以满足比例公平性要求。功率分配结束后,针对每一个用户使用等功率分配方式实现容量分配并实现总功率的最大化。仿真结果表明,所提出的资源分配算法平衡了总容量和公平性之间的折中问题。与最小容量最大化算法相比,满足了用户之间不同的速率要求。相对于总容量最大化算法,容量在用户之间分布更公平。

Genetic strategy based adaptive resource allocation algorithm for multiuser OFDM systems with proportional rate constrains

An adaptive allocation algorithm on the basis of Genetic strategy for subcarrier and power to maximize the sum capacity of multiuser orthogonal frequency division multiplexing(MU-OFDM) systems in a downlink transmission while maintaining proportional fairness is developed.It is a low-complexity suboptimal algorithm which separates subchannel allocation and power allocation.Subchannel allocation is first performed under the condition of an equal power distribution.A genetic strategy then fulfills power allocation among users while maintaining proportional fairness.After the power allocation,each user transmit power is allocated equally to maximize the sum capacity.Simulation results show that the proposed algorithm can offer balance and tradeoff between sum capacity and fairness.Furthermore,it can also satisfy differently required data rate compared to the max-min problem method and the sum capacity is distributed more fairly among users than the sum capacity maximization method.