User Assignment for Wireless Communication Assisted by Reconfigurable Intelligent Surfaces
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摘要: 可重构智能表面(RIS)是一种成本效益高的解决方案,可通过大量低成本的无源反射元件,提高无线通信系统的能源效益。在远场情况时,许多工作都是假设以RIS的中心作为反射点为前提展开研究。对于多用户的远场情况而言,用户位置不同会增加基站(BS)的功耗。该文以BS发射功率为代价矩阵,利用Kuhn-Munkres (KM)算法将用户与RIS单元进行匹配。该用户匹配方法在接收信噪比约束下,可以减少BS的发射功率。仿真结果表明,该文所采用的用户与RIS单元匹配方法与随机RIS单元相比,最多可以减少1%的BS功耗。Abstract: The Reconfigurable Intelligent Surface (RIS) is a new and cost-effective solution for achieving high energy efficiency through massive low-cost passive elements. In the far field case, a lot of work are carried out on the assumption that the center of RIS is the reflection point. In the case of multi-user far field, the difference of user positions will increase the power consumption of Base Station(BS). Users and RIS cells are matched by resorting to Kuhn-Munkres(KM) algorithm in this paper, taking the transmitting power of BS as cost matrix. Under the constraints of SNR, the transmitting power of BS can be reduced by the user assignment method. Simulation results show that the matching method between users and RIS units adopted in this paper can reduce BS power consumption by up to 1% compared with random units of RIS.
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表 1 仿真参数
参数 数值 RIS大小${s_M}$ 0.84 m2 天线增益$G$ 1 波长$\lambda $ 0.1 m 路径损失指数$\alpha $ 2 噪声功率${\sigma ^2}$ –96 dBm 信噪比阈值${r_{0}}$ 48 dB -
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