The tremendous popularity of Internet-of-Things (IoT) applications and wireless devices has prompted a massive increase of indoor wireless traffic. To further explore the potential of indoor IoT wireless networks, creating constructive interactions between indoor wireless transmissions and the built environments becomes necessary. The electromagnetic (EM) wave propagation indoors would be affected by the EM and physical properties of the building material, e.g., its relative permittivity and thickness. In this article, we construct a new multipath channel model by characterizing wall reflection (WR) for an indoor Line-of-Sight (LOS) single-user multiple-input-multiple-output (MIMO) system and derive its ergodic capacity in the closed-form. Based on the analytical results, we define the wireless friendliness of building material based on the spatially averaged indoor capacity and propose a scheme for evaluating the wireless friendliness of building materials. Monte Carlo simulations validate our analytical results and manifest the significant impact of the relative permittivity and thickness of building material on indoor capacity, indicating that the wireless friendliness of building materials should be considered in the planning and optimization of indoor wireless networks. The outcomes of this article would enable appropriate selection of wall materials during building design, thus enhancing the capacity of indoor LOS MIMO communications.

中文翻译：

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作为反射器的建筑材料对室内 LOS MIMO 通信有多友好？


物联网 (IoT) 应用和无线设备的巨大普及促使室内无线流量大幅增加。为了进一步探索室内物联网无线网络的潜力，有必要在室内无线传输和建筑环境之间建立建设性的互动。电磁（EM）波在室内的传播会受到电磁波和建筑材料物理特性（例如相对介电常数和厚度）的影响。在本文中，我们通过表征室内视距（LOS）单用户多输入多输出（MIMO）系统的墙壁反射（WR）来构建新的多径信道模型，并推导其遍历容量封闭形式。基于分析结果，我们基于空间平均室内容量定义了建筑材料的无线友好性，并提出了评估建筑材料无线友好性的方案。蒙特卡洛模拟验证了我们的分析结果，并表明建筑材料的相对介电常数和厚度对室内容量的显着影响，表明在室内无线网络的规划和优化中应考虑建筑材料的无线友好性。本文的成果将有助于在建筑设计过程中适当选择墙体材料，从而提高室内 LOS MIMO 通信的容量。