论文标题
IRS辅助多用户通信系统的能力和最佳资源分配
Capacity and Optimal Resource Allocation for IRS-assisted Multi-user Communication Systems
论文作者
论文摘要
本文研究了智能反射表面（IRS）辅助多用户无线通信系统的基本容量限制。具体而言，在最大数量的IRS重新配置时间的约束下，表征了能力实现非正交多重访问（NOMA）和正交多访问（OMA）传输方案的容量和速率区域。对于NOMA，考虑使用渐近的IRS重新配置时间的理想情况，在这种情况下，通过采用Lagrange二元方法获得了最佳解决方案。受此结果的启发，得出了有限数量的IRS重新配置时间的一般情况的容量区域的内部界限。对于OMA而言，理想情况的最佳传输策略是为每个用户提供最大化的有效渠道功率增益的交替服务。基于此结果，得出了一般情况的速率区域内部结合。最后，提供了数值结果以表明：i）使用IRS可以实现显着的能力和速率区域的改善； ii）通过动态配置IRS反射矩阵可以进一步提高容量增益。
The fundamental capacity limits of intelligent reflecting surface (IRS)-assisted multi-user wireless communication systems are investigated in this paper. Specifically, the capacity and rate regions for both capacity-achieving non-orthogonal multiple access (NOMA) and orthogonal multiple access (OMA) transmission schemes are characterized under the constraints of a maximum number of IRS reconfiguration times. For NOMA, the ideal case with asymptotically large number of IRS reconfiguration times is considered, where the optimal solution is obtained by employing the Lagrange duality method. Inspired by this result, an inner bound of the capacity region for the general case with a finite number of IRS reconfiguration times is derived. For OMA, the optimal transmission strategy for the ideal case is to serve each individual user alternatingly with its effective channel power gain maximized. Based on this result, a rate region inner bound for the general case is derived. Finally, numerical results are provided to show that: i) a significant capacity and rate region improvement can be achieved by using IRS; ii) the capacity gain can be further improved by dynamically configuring the IRS reflection matrix.
