This paper provides recent advances in the area of Internet of Underground Things (IoUT) with emphasis on enabling communication technologies, networking issues, and localization techniques. IoUT is enabled by underground things (sensors), communication technology, and networking protocols. This new paradigm of IoUT facilitates the integration of sensing and communication in the underground environment for various industries, such as oil and gas, agriculture, seismic mapping, and border monitoring. These applications require to gather relevant information from the deployed underground things. However, the harsh underground propagation environment including sand, rock, and watersheds do not allow the use of single communication technology for information transfer between the surface and the underground things. Therefore, various wireless and wired communication technologies are used for underground communication. The wireless technologies are based on acoustic waves, electromagnetic waves, magnetic induction and visible light communication while the wired technologies use coaxial cable and optical fibers. In this paper, state-of-art communication technologies are surveyed, and the respective networking and localization techniques for IoUT are presented. Moreover, the advances and applications of IoUT are also reported. Also, new research challenges for the design and implementation of IoUT are identified.

中文翻译：

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走向地下物联网：系统调查

本文提供了地下物联网 (IoUT) 领域的最新进展，重点介绍了支持通信技术、网络问题和本地化技术。物联网是由地下事物（传感器）、通信技术和网络协议实现的。这种新的 IoUT 范式促进了地下环境中各种行业的传感和通信的集成，例如石油和天然气、农业、地震测绘和边境监测。这些应用程序需要从部署的地下事物中收集相关信息。然而，包括沙子、岩石、流域在内的恶劣的地下传播环境不允许使用单一的通信技术在地表和地下事物之间进行信息传递。所以，各种无线和有线通信技术用于地下通信。无线技术基于声波、电磁波、磁感应和可见光通信，而有线技术使用同轴电缆和光纤。在本文中，调查了最先进的通信技术，并介绍了 IoUT 的相应网络和定位技术。此外，还报告了 IoUT 的进展和应用。此外，还确定了 IoUT 设计和实施的新研究挑战。在本文中，调查了最先进的通信技术，并介绍了 IoUT 的相应网络和定位技术。此外，还报告了 IoUT 的进展和应用。此外，还确定了 IoUT 设计和实施的新研究挑战。在本文中，调查了最先进的通信技术，并介绍了 IoUT 的相应网络和定位技术。此外，还报告了 IoUT 的进展和应用。此外，还确定了 IoUT 设计和实施的新研究挑战。