基于时间反演的上行NOMA系统能效优化算法

为了解决上行非正交多址接入(non-orthogonal multiple access, NOMA)系统在多径环境下传输效率较低问题, 提出了一种基于时间反演(time reversal, TR)的上行NOMA网络资源分配算法。首先, 利用TR技术独特的空时聚焦特性, 增大信号的接收强度。其次, 考虑用户最小传输速率约束和用户最大发射功率约束, 建立了系统能效最大化资源分配模型。然后, 利用分式规划理论和连续凸近似方法, 将所提出的非凸优化问题转化为凸优化问题, 并利用拉格朗日对偶理论求得全局最优解。仿真结果表明, 相较于传统算法, 所提出的算法具有较好的能效。

Energy efficiency optimization algorithm for uplink NOMA systems with time reversal

In order to solve the problem of low transmission efficiency in non-orthogonal multiple access(NOMA) system, a time reversal(TR) based uplink NOMA network resource allocation algorithm is proposed. Firstly, the signal receiving intensity of user is improved by the spatial-temporal focusing of the TR technology. Next, considering the user’s minimum transmission rate constraint and the user’s maximum transmission power constraint, a resource allocation model for maximizing system energy efficiency is established. Then, by using fractional programming theory and continuous convex approximation method, the proposed non-convex optimization problem is transformed into a convex optimization problem, and the global optimal solution is obtained by using Lagrangian duality theory. Simulation results show that compared with traditional algorithms, the proposed algorithm has better energy efficiency.