In this paper, we investigate the outage performance of an intelligent reflecting surface (IRS)-assisted non-orthogonal multiple access (NOMA) uplink, in which a group of the surface reflecting elements are configured to boost the signal of one of the user equipments (UEs), while the remaining elements are used to boost the other UE. By approximating the received powers as Gamma random variables, tractable expressions for the outage probability under NOMA interference cancellation are obtained. We evaluate the outage over different splits of the elements and varying pathloss differences between the two UEs. The analysis shows that for small pathloss differences, the split should be chosen such that most of the IRS elements are configured to boost the stronger UE, while for large pathloss differences, it is more beneficial to boost the weaker UE. Finally, we investigate a robust selection of the elements' split under the criterion of minimizing the maximum outage between the two UEs.
翻译:在本文中,我们调查了一个智能反射表面(IRS)辅助非垂直多存取(NOMA)上链接的失灵性能,其中一组表面反射元素被配置以提升一个用户设备(UES)的信号,而其余元素则用于促进另一个UE。通过将接收的功率近似于伽玛随机变量,我们获得了NOMA干扰取消下断电概率的可移动表达式。我们评估了元素不同分割的断流和两个UES之间的不同路径差。分析显示,对于小路径差差异,应该选择一个部分反射元素,以便大多数IRS元素被配置为增强UE,而对于大路径差则更有利于增强UE。最后,我们根据将两个UES的最大输出最小化的标准,调查了对元素进行分解的可靠选择。