基于功率最小化的IRS辅助上行NOMA系统资源分配方法

IRS-aided Uplink NOMA Systems Resource Allocation Scheme Based on Power Minimization

对于智能反射面(IRS)辅助的单簇上行非正交多址接入(NOMA)系统,该文提出一种最小化系统总功率的资源分配方案。首先构建最小化总功率的优化问题,优化参数为用户功率和IRS相移;然后,推导单个用户所需的功率与信道、用户的速率需求以及IRS相移之间的关系,将功率与相移的联合优化问题分解为多个包含单个参数的子优化问题;其次,采用迭代的方法求解所有的IRS相移,在每次迭代过程中,依次求解包含单个参数的子优化问题;最后,根据迭代得到的IRS相移计算出每个用户所需的最低功率。仿真结果显示,在速率需求相同的条件下,所提方案所需的总功率低于相同场景中的已有方案。

A resource allocation scheme to minimize the total power is proposed for IRS-Assisted single cluster uplink Non-Orthogonal Multiple Access(NOMA)systems.Firstly,the optimization problem is constructed to minimize the total power,and the parameters are power for each user and Intelligent Reflecting Surface(IRS)phase shifts.Secondly,the relationship among the power required by single user,the channel,the user's rate requirements and IRS phase shifts is deduced.The joint optimization problem of power and phase shifts is decomposed into several sub-optimization problems with a single parameter.Then,all IRS phase shifts are solved by an iterative method,and the sub-optimization problems with a single parameter are solved in turn during each iteration.Finally,the minimum power required by each user is calculated based on the IRS phase shifts obtained by iteration.Simulation results show that the total power of the proposed scheme is lower than that of existing schemes in the same scenario.