Open Access
Design, implementation, and empirical validation of an IoT smart irrigation system for fog computing applications based on Lora and Lorawan sensor nodes
(MDPI, 2020) Froiz Míguez, Iván; López Iturri, Peio; Fraga Lamas, Paula; Celaya Echarri, Mikel; Blanco Novoa, Óscar; Azpilicueta Fernández de las Heras, Leyre; Falcone Lanas, Francisco; Fernández Caramés, Tiago M.; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Institute of Smart Cities - ISC; Ingeniería Eléctrica, Electrónica y de Comunicación
Climate change is driving new solutions to manage water more efficiently. Such solutions involve the development of smart irrigation systems where Internet of Things (IoT) nodes are deployed throughout large areas. In addition, in the mentioned areas, wireless communications can be difficult due to the presence of obstacles and metallic objects that block electromagnetic wave propagation totally or partially. This article details the development of a smart irrigation system able to cover large urban areas thanks to the use of Low-Power Wide-Area Network (LPWAN) sensor nodes based on LoRa and LoRaWAN. IoT nodes collect soil temperature/moisture and air temperature data, and control water supply autonomously, either by making use of fog computing gateways or by relying on remote commands sent from a cloud. Since the selection of IoT node and gateway locations is essential to have good connectivity and to reduce energy consumption, this article uses an in-house 3D-ray launching radio-planning tool to determine the best locations in real scenarios. Specifically, this paper provides details on the modeling of a university campus, which includes elements like buildings, roads, green areas, or vehicles. In such a scenario, simulations and empirical measurements were performed for two different testbeds: a LoRaWAN testbed that operates at 868 MHz and a testbed based on LoRa with 433 MHz transceivers. All the measurements agree with the simulation results, showing the impact of shadowing effects and material features (e.g., permittivity, conductivity) in the electromagnetic propagation of near-ground and underground LoRaWAN communications. Higher RF power levels are observed for 433 MHz due to the higher transmitted power level and the lower radio propagation losses, and even in the worst gateway location, the received power level is higher than the sensitivity threshold (–148 dBm). Regarding water consumption, the provided estimations indicate that the proposed smart irrigation system is able to reduce roughly 23% of the amount of used water just by considering weather forecasts. The obtained results provide useful guidelines for future smart irrigation developers and show the radio planning tool accuracy, which allows for optimizing the sensor network topology and the overall performance of the network in terms of coverage, cost, and energy consumption.
Open Access
An IoT framework for SDN based city mobility
(Springer, 2021) Al-Rahamneh, Anas; Astrain Escola, José Javier; Villadangos Alonso, Jesús; Klaina, Hicham; Picallo Guembe, Imanol; López Iturri, Peio; Falcone Lanas, Francisco; Estatistika, Informatika eta Matematika; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Institute of Smart Cities - ISC; Estadística, Informática y Matemáticas; Ingeniería Eléctrica, Electrónica y de Comunicación
The Internet of Things (IoT) is becoming more widespread, with global application in a wide range of commercial sectors, utilizing a variety of technologies for customized use in specific environments. The combinationof applications and protocolsand the unique requirements of each environment present a significant challenge for IoT applications, necessitating communication and message exchange support. This paper presents a proposed SDN-based edge smart bypass/ multiprotocol switching for bicycle networks that supports functionalities of coordination of various wireless transmission protocols. A performance assessment will be presented, addressing a comparison between the different protocols (LoRaWAN vs. Sigfox) in terms radio coverage.
Open Access
Wireless characterization and assessment of an UWB-Based system in industrial environments
(IEEE, 2021) Picallo Guembe, Imanol; López Iturri, Peio; Klaina, Hicham; Glaría Ezker, Guillermo; Sáez de Jaúregui Urdanoz, Félix; Zabalza Cestau, José Luis; Azpilicueta Fernández de las Heras, Leyre; Falcone Lanas, Francisco; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Institute of Smart Cities - ISC; Ingeniería Eléctrica, Electrónica y de Comunicación; Gobierno de Navarra / Nafarroako Gobernua
The advent of Indsutrial Internet of Things is one of the main drivers for the implementation of Industry 4.0 scenarios and applications, in which wireless communication systems play a key role in terms of flexibility, mobility and deployment capabilities. However, the integration of wireless communication systems poses challenges, owing to variable path loss conditions and interference impact. In this work, an Ultra-Wideband (UWB) system for indoor location in very large, complex industrial scenarios is presented. Precise wireless channel characterization for the complete volume of a logistical plant is performed, based on 3D hybrid ray launching approximation, in order to aid network node design process. Wireless characterization, implementation and measurement results are obtained for both 4 GHz and 6 GHz frequency bands, considering different densities of scatterers within the scenario under test. Time domain estimation results have been obtained and compared with time of flight measurement results, showing good agreement. The proposed methodology enables to perform system design and performance tasks, analyzing the impact of variable object density conditions in wireless channel response, providing accurate time of flight estimations without the need of complex channel sounder systems, aiding in optimal system planning and implementation.
Open Access
Empirical and modeling approach for environmental indoor RF-EMF assessment in complex high-node density scenarios: public shopping malls case study
(IEEE, 2021) Celaya Echarri, Mikel; Azpilicueta Fernández de las Heras, Leyre; Ramos, Victoria; López Iturri, Peio; Falcone Lanas, Francisco; Ingeniería Eléctrica, Electrónica y de Comunicación; Institute of Smart Cities - ISC; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
This work provides an intensive and comprehensive in-depth study from an empirical and modeling approach of the environmental radiofrequency electromagnetic fields (RF-EMF) radiation exposure in public shopping malls, as an example of an indoor high-node user density context aware environment, where multiple wireless communication systems coexist. For that purpose, current personal mobile communications (2G-5G FR 1) as well as Wi-Fi services (IEEE 802.11n/ac) have been precisely analyzed in order to provide clear RF-EMF assessment insight and to verify compliance with established regulation limits. In this sense, a complete measurements campaign has been performed in different countries, with frequency-selective exposimeters (PEMs), providing real empirical datasets for statistical analysis and allowing discussion and comparison regarding current health effects and safety issues between some of the most common RF-EMF exposure safety standards: ICNIRP 2020 (Spain), IEEE 2019 (Mexico) and a more restrictive regulation (Poland). In addition, environmental RF-EMF exposure assessment simulation results, in terms of spatial E-field characterization and Cumulative Distribution Function (CDF) probabilities, have been provided for challenging incremental high-node user dense scenarios in worst case conditions, by means of a deterministic in-house 3D Ray-Launching (3D-RL) RF-EMF safety simulation technique, showing good agreement with the experimental measurements. Finally, discussion highlighting the contribution and effects of the coexistence of multiple heterogenous networks and services for the environmental RF-EMF radiation exposure assessment has been included, showing that for all measured results and simulated cases, the obtained E-Field levels are well below the exposure limits established in the internationally accepted standards and guidelines. In consequence, the obtained results and the presented methodology could become a starting point to stablish the RF-EMF assessment basis of future complex heterogeneous 5G FR 2 developments on the millimeter wave (mmWave) frequency range, where massive high-node user density networks are expected.
Open Access
Aggregator to electric vehicle LoRaWAN based communication analysis in vehicle-to-grid systems in smart cities
(IEEE, 2020) Klaina, Hicham; Picallo Guembe, Imanol; López Iturri, Peio; Astrain Escola, José Javier; Azpilicueta Fernández de las Heras, Leyre; Falcone Lanas, Francisco; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Estatistika, Informatika eta Matematika; Institute of Smart Cities - ISC; Ingeniería Eléctrica, Electrónica y de Comunicación; Estadística, Informática y Matemáticas
Recently, there has been growing attention to the power grid management due to the increasing concerns on global warming. With the advancement in electric vehicles (EV) industry and the evolution in batteries, EVs become an important contributor to the grid with capability of bidirectional power exchange with the grid. In this context, Vehicle-to-Grid (V2G) systems enable multiple functionalities between EVs and the corresponding aggregator. Thus, reliable, long-range communication capabilities between aggregator and EVs is compulsory. In this paper, wireless channel analysis for aggregator and electrical vehicle communication using Long-Range Wide Area Network (LoRaWAN) technology in V2G is presented, in order to test a low-cost solution with large coverage and reduced power consumption profile. Wireless channel and system-level measurements have been performed in a real urban scenario between EV's charging station in Pamplona (Spain) and a vehicle in motion using LoRaWAN 868 MHz devices. Wireless channel characterization is performed by implementing a full 3D urban scenario model, including elements such as buildings, vehicles, users and urban infrastructure such as lamp posts and benches. By means of in-house developed 3D Ray Launching algorithm with hybrid simulation capabilities, estimations of received power levels, signal to noise ratio and time domain parameters have been obtained, for the complete volume of the scenario under test in dense urban conditions. V2G end to end communication has been validated by implementing an intra-vehicle Controller Area Network-BUS (CAN BUS) data gathering system connected to the vehicle LoRaWAN transceiver and subsequently, to a cloud-based web service. The results show that the accurate deterministic based radio channel analysis enables to optimize the network design of LoRaWAN networks in a vehicular environment, considering inter-vehicular and infrastructure links, enabling scalable, low cost end to end data exchange for the deployment of ancillary V2G services.
Open Access
Analysis and implementation of wireless communications systems and IoT with human body interference in inhomogeneous environments
(2021) Picallo Guembe, Imanol; Klaina, Hicham; Azpilicueta Fernández de las Heras, Leyre; López Iturri, Peio; Falcone Lanas, Francisco; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
The Integration of wireless communication systems is one of the main drivers of the development of the future connected society. However, this will cause challenges due to the non-static channel effect and interference impact. For this reason, a research work is proposed that enables to obtain optimal node location in relation to radio planning tasks (coverage/capacity analysis, number of lost packets, devices’ consumption...), as well as to characterize the environments considering obstacles and human body being, in terms of the received power level in the complete simulation volume and at the time domain level. This will help derive wireless channel models taking into account real channel variations to deploy a Wireless Sensor Network (WSN) and reduce the impact on wireless systems performance.
Open Access
Towards environmental RF-EMF assessment of mmwave high-node density complex heterogeneous environments
(MDPI, 2021) Celaya Echarri, Mikel; Azpilicueta Fernández de las Heras, Leyre; Rodríguez Corbo, Fidel Alejandro; López Iturri, Peio; Ramos González, Victoria; Alibakhshikenari, Mohammad; Shubair, Raed M.; Falcone Lanas, Francisco; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Institute of Smart Cities - ISC; Ingeniería Eléctrica, Electrónica y de Comunicación
The densification of multiple wireless communication systems that coexist nowadays, as well as the 5G new generation cellular systems advent towards the millimeter wave (mmWave) frequency range, give rise to complex context-aware scenarios with high-node density heterogeneous networks. In this work, a radiofrequency electromagnetic field (RF-EMF) exposure assessment from an empirical and modeling approach for a large, complex indoor setting with high node density and traffic is presented. For that purpose, an intensive and comprehensive in-depth RF-EMF E-field characterization study is provided in a public library study case, considering dense personal mobile communications (5G FR2 @28 GHz) and wireless 802.11ay (@60 GHz) data access services on the mmWave frequency range. By means of an enhanced in-house deterministic 3D ray launching (3D-RL) simulation tool for RF-EMF exposure assessment, different complex heterogenous scenarios of high complexity are assessed in realistic operation conditions, considering different user distributions and densities. The use of directive antennas and MIMO beamforming techniques, as well as all the corresponding features in terms of radio wave propagation, such as the body shielding effect, dispersive material properties of obstacles, the impact of the distribution of scatterers and the associated electromagnetic propagation phenomena, are considered for simulation. Discussion regarding the contribution and impact of the coexistence of multiple heterogeneous networks and services is presented, verifying compliance with the current established international regulation limits with exposure levels far below the aforementioned limits. Finally, the proposed simulation technique is validated with a complete empirical campaign of measurements, showing good agreement. In consequence, the obtained datasets and simulation estimations, along with the proposed RF-EMF simulation tool, could be a reference approach for the design, deployment and exposure assessment of the current and future wireless communication technologies on the mmWave spectrum, where massive high-node density heterogeneous networks are expected.
Open Access
5G spatial modeling of personal RF-EMF assessment within aircrafts cabin environments
(IEEE, 2022) Celaya Echarri, Mikel; Azpilicueta Fernández de las Heras, Leyre; Rodríguez Corbo, Fidel Alejandro; López Iturri, Peio; Shubair, Raed M.; Ramos González, Victoria; Falcone Lanas, Francisco; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Institute of Smart Cities - ISC; Ingeniería Eléctrica, Electrónica y de Comunicación
Recently, new wireless communication systems within aircrafts cabins have drawn higher attention due to the growing demand of passenger services and applications and their corresponding requirements and constraints. In this regard, the fifth generation (5G) of wireless communication becomes an attractive and promising alternative to enable aircraft passengers' comfort and entertainment along the flight, considering its potential benefits in term of high data transfers and low latencies. Nevertheless, general population concern about radio frequency electromagnetic fields (RF-EMF) safety in general and, in particular to the environmental exposure at which we are all exposed in these flights, increases at the same time. Thus, in this work, we present an experimental campaign of measurements for current passengers' environmental exposure assessment, performed in different real generalizable type of flights and aircrafts' cabins, in order to provide current RF-EMF exposure insight within these complex heterogeneous environments. In addition, worst-case uplink 5G scenarios, where all 5G cellular handsets of the passengers operate at the same time, have been simulated by means of an in-house developed 3D Ray Launching (3D-RL) deterministic technique. Before takeoff and after landing, critical scenarios with the aircrafts' doors closed have been selected and assessed considering different types of modeled aircrafts full of passengers, considering 5G frequency range 2 (5G-FR2) operating links. The obtained results show that the operation frequency and the morphology and topology of the aircraft cabin have a great influence in the environmental RF-EMF passengers' spatial distribution and overall exposure, but not exceeding, even in worst case conditions, the international established regulatory limits. © 2022 IEEE.
Open Access
Enabling anything to anything connectivity within urban environments towards cognitive frameworks
(IEEE, 2024-08-23) Picallo Guembe, Imanol; Klaina, Hicham; López Iturri, Peio; Azpilicueta Fernández de las Heras, Leyre; Celaya Echarri, Mikel; Astrain Escola, José Javier; Villadangos Alonso, Jesús; Falcone Lanas, Francisco; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoa eta Telekomunikazio Ingeniaritza; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika; Ciencias; Zientziak; Institute of Smart Cities - ISC
The evolution from Smart Cities towards Cognitive Cities is enabled, among others, by the use of flexible and adaptive communication systems, capable of providing high levels of interactivity among multiple systems and users. In this work, wireless connectivity in full volumetric scale is analyzed, in order to provide wireless links between any device/user within the scenario, spanning to different applications from vehicular connectivity at different levels or infrastructure related communications, among others.
Open Access
Building decentralized fog computing-based smart parking systems: from deterministic propagation modeling to practical deployment
(IEEE, 2020) Celaya Echarri, Mikel; Froiz Míguez, Iván; Azpilicueta Fernández de las Heras, Leyre; López Iturri, Peio; Falcone Lanas, Francisco; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Institute of Smart Cities - ISC; Ingeniería Eléctrica, Electrónica y de Comunicación
The traditional process of finding a vacant parking slot is often inefficient: it increases driving time, traffic congestion, fuel consumption and exhaust emissions. To address such problems, smart parking systems have been proposed to help drivers to find available parking slots faster using latest sensing and communications technologies. However, the deployment of the communications infrastructure of a smart parking is not straightforward due to multiple factors that may affect wireless propagation. Moreover, a smart parking system needs to provide not only accurate information on available spots, but also fast responses while guaranteeing the system availability even in the case of lacking connectivity. This article describes the development of a decentralized low-latency smart parking system: from its conception, design and theoretical simulation, to its empirical validation. Thus, this work first characterizes a real-world scenario and proposes a fog computing and Internet of Things (IoT) based communications architecture to provide smart parking services. Next, a thorough analysis on the wireless channel properties is carried out by means of an in-house developed deterministic 3D-Ray Launching (3D-RL) tool. The obtained results are validated through a real-world measurement campaign and then the communications architecture is implemented by using ZigBee sensor nodes. The implemented architecture also makes use of Bluetooth Low Energy beacons, an Android app, a decentralized database and fog computing gateways, whose performance is evaluated in terms of response latency and processing rate. Results show that the proposed system is able to deliver information to the drivers fast, with no need for relying on remote servers. As a consequence, the presented development methodology and communications evaluation tool can be useful for future smart parking developers, which can determine the optimal locations of the wireless transceivers during the simulation stage and then deploy a system that can provide fast responses and decentralized services.