功率分配是非正交多址系统(NOMA)资源分配中的一个重要研究问题。最优迭代注水功率分配算法能提高系统性能,但是算法复杂度较高。提出一种低复杂度的功率分配算法,首先对子载波采用注水原理得到总的复用功率,然后在单个子载波上叠加用户间采用分数阶功率分配方法进行功率再分配。通过仿真分析,与最优迭代注水功率分配算法相比,该算法在性能损失不超过3%的情况下,大幅减低了计算复杂度。
Power allocation is an important research issue of resource allocation in non-orthogonal multiple access system. Optimal water-filling power allocation algorithm can improve the system performance, but the complexity of the algorithm is relatively high.This paper presents a low complexity power allocation algorithm. Firstly, the algorithm uses water-filling principle to subcarriers in order to get the total multiplexed power. Then the fractional transmission power allocation algorithm is used to reallocate the total multiplexed power for multiplexed users on single subcarrier. The simulation result shows that the proposed algorithm can obviously reduce the computational complexity under the circumstance of the performance loss of less than 3% compared with the optimal water-filling transmission power allocation.