基于能量效率的星地NOMA网络功率分配算法

Power Allocation in Satellite-Terrestrial NOMA Network Based on Energy Efficiency

为了提高卫星地面网络的能量效率和用户服务公平性,减小系统内干扰,本文提出了一种基于能量效率的星地非正交多址(Non-Orthogonal Multiple Access,NOMA)网络功率分配算法.首先基于最大化系统能量效率原则,设计了一种卫星用户选择和地面用户分组策略.其次以系统内干扰、最大发射功率以及用户服务质量为约束条件,建立了地面和卫星功率分配优化模型,利用连续凸近似和Dinkelbach法,将基于能量效率的非凸问题转化为凸优化问题,并利用拉格朗日对偶法和次梯度迭代法求得解析解.研究结果表明,当基站最大发射功率为50 dBm时,相对于贪婪算法策略,所提配对策略能量效率提升约13.4%,相对于固定相关度策略,所提配对策略能量效率提升约8.2%,相比于正交多址功率分配策略,所提联合最优功率分配算法系统能量效率提升约10.1%.

In order to improve the energy efficiency and service fairness of satellite-terrestrial networks,and reducing the intra-system interference,this paper proposes an energy-efficiency power allocation algorithm for satellite-terrestrial non-orthogonal multiple access networks.Firstly,we design a strategy for satellite users selection and terrestrial users grouping based on the principle of maximizing system energy efficiency.Secondly,we establish a satellite and terrestrial power alloca-tion optimization model under the constraints of the intra-system interference,maximum emission power,and users service quality.Then,the non-convex problem based on energy efficiency is converted into the convex optimization problem by the successive convex approximation and Dinkelbach method.The analytical solutions are obtained by the Lagrangian dual and subgradient iteration approach.The results show that the energy efficiency of the proposed pairing strategy improves by about 13.4%relative to the greedy algorithm strategy and improves by about 8.2%relative to the fixed correlation strategy when the maximum emission power of the base station is 50 dBm.And the energy efficiency of the proposed joint optimal power allocation algorithm increases by about 14.5%compared to the orthogonal multiple access power allocation strategy.