针对已有算法对系统容量和高公平性兼顾较差的情况,提出了一种满足公平性的系统容量最大化资源分配算法.在子载波分配中通过建立信道效率控制模型,给当前用户分配信道效率最高的子载波,将信道增益低于门限值的子载波重新分配,改进了最大化最小(max-min)用户速率模型.在功率分配中将系统模型转化成用注水线表示的数学模型,首先求解各用户的注水线,再求解各用户的功率分配,保证了用户间比例公平性.两种信噪比情形下的仿真和分析表明,整个方案计算复杂度稍低,系统容量获得较大提升,并且用户间的公平性始终为1.
Existing algorithms couldn't balance system capacity and high fairness well,so a multi-user rate adaptive allocation algorithm was proposed to maximize the capacity of OFDMA system under proportional fairness.Improved maximize the minimum(max-min) user rate model was proposed,the current user was allocated the highest efficiency subcarrier according to the channel efficiency control parameter.If some allocated subcarrier's channel gain was lower than the threshold value,which would be reallocated to another user whose channel gain was highest.Power allocation model was converted into expression of water-filling line; every user's power allocation was resolved according to the resolved water-filling line.Simulation results and analysis show that the proposed scheme can achieve higher capacity and perfect fairness in a variety of SNR cases,while requiring slightly less computation.