新的NOMA功率分配策略

New NOMA power allocation strategy

下行链路非正交多址接入技术(NOMA)可以有效提高频谱效率和数据速率,已经广泛应用到第5代通信技术的研究中。为了确保用户的服务质量,针对提高边缘小区用户公平性问题,提出一种新的功率分配策略。根据比例公平方法,在保证每个用户最低数据速率约束下,最大化复用用户中公平性最差的用户的比例公平因子。然后,将此非凸的目标函数转换成凸函数,用KKT最优约束条件求出问题的最优解。仿真证明,新的基于NOMA的功率分配方案,系统性能优于传统的正交多址接入(OMA)技术。

Non-orthogonal multiple access（NOMA） has been widely used in the research of the fifth generation communication, due to the advantages of improving the spectrum efficiency and data rate. In order to guarantee the service of users, a new power allocation strategy was proposed to improve the fairness of users in the cell edge. According to the proportional fairness method, the goal was to maximize the proportionality fairness factor among the users with the least fairness in multiplexed users. The nonconvex objective function was transformed into convex function, and the optimal solution of problem was obtained by KKT optimal constraint condition. Simulation results show that the new NOMA-based power allocation strategy proposed outperforms the traditional orthogonal multiple access technology（OMA）.