标题： 室内密集空间中混合静态与可重构超表面的部署：需要多少可重构性？ 显示英文标题

标题： Mixed Static and Reconfigurable Metasurface Deployment in Indoor Dense Spaces: How Much Reconfigurability is Needed?

摘要： 本文研究了如何部署超表面以在存在大量阻挡物的毫米波（mmWave）室内密集环境中提供高数据速率。 这些表面可以是具有固定相移的静态超表面（SMSs），也可以是能够重新配置其相移以服务于当前用户的可重构智能表面（RISs）。后者伴随着功率、布线和信号成本的增加。 为了了解可重构性对网络性能的影响，我们基于可行点跟踪连续凸逼近方法提出了一种迭代算法。 我们将表面的类型和相移以及分配给每个用户设备的时间比例联合优化，以最大化网络达到的最小数据速率。 我们的数值结果显示，随着更多RISs的引入，最小数据速率会提高，但在某个点之后增益会减弱。因此，并非总是需要引入更多的可重构性。 另一个结果表明，要达到使用22个SMSs实现的数据速率，至少需要18个RISs。这表明，当部署大量RISs的成本较高时，作为一种低成本的替代方案，可以通过密集部署更多的SMSs来达到相同的数据速率。 显示英文摘要

摘要： In this paper, we investigate how metasurfaces can be deployed to deliver high data rates in a millimeter-wave (mmWave) indoor dense space with many blocking objects. These surfaces can either be static metasurfaces (SMSs) that reflect with fixed phase-shifts or reconfigurable intelligent surfaces (RISs) that can reconfigure their phase-shifts to the currently served user. The latter comes with an increased power, cabling, and signaling cost. To see how reconfigurability affects the network performance, we propose an iterative algorithm based on the feasible point pursuit successive convex approximation method. We jointly optimize the types and phase-shifts of the surfaces and the time portion allocated to each user equipment to maximize the minimum data rate achieved by the network. Our numerical results demonstrate that the minimum data rate improves as more RISs are introduced but the gain diminishes after some point. Therefore, introducing more reconfigurability is not always necessary. Another result shows that to reach the same data rate achieved by using 22 SMSs, at least 18 RISs are needed. This suggests that when it is costly to deploy many RISs, as an inexpensive alternative solution, one can reach the same data rate just by densely deploying more SMSs.