Radio Wave Propagation and WSN Deployment in Complex Utility Tunnel Environments

Abstract

The significant growth of wireless communications systems in the last years has led to the adoption of a wide range of applications not only for the general public but, also, including utilities and administrative authorities. In this context, the notable expansion of new services for smart cities requires, in some specific cases, the construction of underground tunnels in order to enable the maintenance and operation works of utilities, as well as to reduce the visual impact within the city center. One of the main challenges is that, inherently, underground service tunnels lack coverage from exterior wireless communication systems, which can be potentially dangerous for maintenance personnel working within the tunnels. Accordingly, wireless coverage should be deployed within the underground installation in order to guarantee real-time connectivity for safety maintenance, remote surveillance or monitoring operations. In this work, wireless channel characterization for complex urban tunnel environments was analyzed based on the assessment of LoRaWAN and ZigBee technologies operating at 868 MHz. For that purpose, a real urban utility tunnel was modeled and simulated by means of an in-house three-dimensional ray-launching (3D-RL) code. The utility tunnel scenario is a complex and singular environment in terms of radio wave propagation due to the limited dimensions and metallic elements within it, such as service trays, user pathways or handrails, which were considered in the simulations. The simulated 3D-RL algorithm was calibrated and verified with experimental measurements, after which, the simulation and measurement results showed good agreement. Besides, a complete wireless sensor network (WSN) deployment within the tunnels was presented, providing remote cloud data access applications and services, allowing infrastructure security and safety work conditions. The obtained results provided an adequate radio planning approach for the deployment of wireless systems in complex urban utility scenarios, with optimal coverage and enhanced quality of service.

Engineering Project: The Method to Solve Practical Problems for the Monitoring and Control of Driver-Less Electric Transport Vehicles in the Underground Mines

“…In 2021, Yang et al [86] improved the communication function of ZigBee WSN based on the background of a mine. Although Celaya-Echarri et al [87] also proposed several other monitoring methods for the underground environment, there is no doubt that ZigBee WSN have greater superiority in information transmission of the underground environment.…”

Towards Environmental RF-EMF Assessment of mmWave High-Node Density Complex Heterogeneous Environments

“…The proposed in-house 3D-RL algorithm is based on Geometrical Optics (GO) and the Uniform Theory of Diffraction (UTD). It has been previously validated in different indoor/outdoor complex environments [31,32] for different applications, such as vehicular communications [33,34], Intelligent Transportation Systems (ITS) [35][36][37], interference analysis [38,39], Wireless Local Area Networks (WLAN) [40,41], Wireless Sensor Networks (WSNs) [42,43] or Public Land Mobile Networks (PLMN) [23,24], among others. These applications have been validated for different operating frequencies (from mid-bands to mmWave frequency bands) and different wireless communication system configurations, achieving, in general, a Root Mean Square Error (RMSE) of 3-6 dB, an absolute mean error of 4-5 dB and a Standard Deviation (SD) of 1-7 dB.…”

Engineering Project: The Method to solve practical problems for the monitoring and control of Driver-less Electric Transport Vehicles in the underground mines

“…And in 2021, Y. Yang et al [52] improved the communication function of ZigBee WSN based on the background of a mine. Although, M. Celaya-Echarri et al [53] also proposed several other monitoring methods for the underground environment, there is no doubt that, ZigBee WSN have greater superiority in information transmission of the underground environment.…”