Open Access
Design and performance analysis of wireless body area networks in complex indoor e-Health hospital environments for patient remote monitoring
(SAGE, 2016) Aguirre Gallego, Erik; López Iturri, Peio; Azpilicueta Fernández de las Heras, Leyre; Rivarés Garasa, Carmen; Astrain Escola, José Javier; Villadangos Alonso, Jesús; Falcone Lanas, Francisco; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa; Ingeniería Matemática e Informática; Matematika eta Informatika Ingeniaritza
In this article, the design and performance analysis of wireless body area network–based systems for the transmission of medical information readable in an android-based application deployed within complex indoor e-Health scenarios is presented. The scenario under analysis is an emergency room area, where a patient is being monitored remotely with the aid of wearable wireless sensors placed at different body locations. Due to the advent of Internet of Things, in the near future a cloud of a vast number of wireless devices will be operating at the same time, potentially interfering one another. Ensuring good performance of the deployed wireless networks in this kind of environment is mandatory and obtaining accurate radio propagation estimations by means of a computationally efficient algorithm is a key issue. For that purpose, an in-house three-dimensional ray launching algorithm is employed, which provides radio frequency power distribution values, power delay profiles, and delay spread values for the complete volume of complex indoor scenarios. Using this information together with signal-to-noise estimations and link budget calculations, the most suitable wireless body area network technology for this context is chosen. Additionally, an in-house developed human body model has been developed in order to model the impact of the presence of monitored patients. A campaign of measurements has been carried out in order to validate the obtained simulation results. Both the measurements and simulation results illustrate the strong influence of the presented scenario on the overall performance of the wireless body area networks: losses due to material absorption and the strong influence of multipath components due to the great number of obstacles and the presence of persons make the use of the presented method very useful. Finally, an android-based application for the monitoring of patients is presented and tested within the emergency room scenario, providing a flexible solution to increase interactivity in health service provision.
Open Access
Evaluation of electromagnetic interference and exposure assessment from s-Health solutions based on Wi-Fi devices
(Hindawi Publishing Corporation, 2015) Miguel Bilbao, Silvia de; Aguirre Gallego, Erik; Azpilicueta Fernández de las Heras, Leyre; Roldán Madroñero, José; Ramos González, Victoria; Falcone Lanas, Francisco; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
In the last decade the number of wireless devices operating at the frequency band of 2.4GHz has increased in several settings, such as healthcare, occupational, and household. In this work, the emissions fromWi-Fi transceivers applicable to context aware scenarios are analyzed in terms of potential interference and assessment on exposure guideline compliance. Near field measurement results as well as deterministic simulation results on realistic indoor environments are presented, providing insight on the interaction between theWi-Fi transceiver and implantable/body area network devices as well as other transceivers operating within an indoor environment, exhibiting topological and morphological complexity. By following approaches (near field estimation/deterministic estimation), colocated body situations as well as large indoor emissions can be determined.The results show in general compliance with exposure levels and the impact of overall network deployment, which can be optimized in order to reduce overall interference levels while maximizing system performance.
Open Access
Analysis of radio wave propagation for ISM 2.4GHz wireless sensor networks in inhomogeneous vegetation environments
(2014) Azpilicueta Fernández de las Heras, Leyre; López Iturri, Peio; Aguirre Gallego, Erik; Astrain Escola, José Javier; Villadangos Alonso, Jesús; Falcone Lanas, Francisco; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa; Ingeniería Matemática e Informática; Matematika eta Informatika Ingeniaritza
The use of wireless networks has been extended in an exponential growing due to the improvement in terms of battery life and low consumption of the devices. However, it is highly important to conduct previous radio propagation analysis when deploying a wireless sensor network. These studies are necessary to perform an estimation of the range coverage, in order to optimize the distance between devices in an actual network deployment. In this work, the radio channel characterization for ISM 2.4GHz Wireless Sensor Networks (WSN) in an inhomogeneous vegetation environment has been analyzed. The impact of topology as well as morphology of the environment is assessed by means of an in-house developed 3D Ray Launching code, to emulate the realistic operation in the framework of the scenario. Experimental results gathered from a measurements campaign conducted by deploying a ZigBee Wireless Sensor Network, are analyzed and compared with simulations in this paper. The scenario where this network is intended to operate is a combination of buildings and diverse vegetation species. To gain insight in the effects of radio propagation, a simplified vegetation model has been developed, considering the material parameters and simplified geometry embedded in the simulation scenario. The use of deterministic tools can aid to know the impact of the topological influence in the deployment of the optimal Wireless Sensor Network in terms of capacity, coverage and energy consumption, making the use of these systems attractive for multiple applications in inhomogeneous vegetation environments.
Open Access
Aplicación de sistemas RFID y su implementación en el sector logístico
(2010) Aguirre Gallego, Erik; Falcone Lanas, Francisco; Escuela Técnica Superior de Ingenieros Industriales y de Telecomunicación; Telekomunikazio eta Industria Ingeniarien Goi Mailako Eskola Teknikoa; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
Este proyecto se centra en la tecnología RFID aplicada al ámbito logístico y pretende ofrecer tanto nociones básicas de la tecnología y sus aplicaciones en este ámbito, como un completo estudio radioeléctrico tanto teórico como practico de diferentes entornos. Para transmitir los conceptos básicos, se presenta la utilidad de este sistema en logística apoyada en casos de estudio previos y todos los conceptos teóricos necesarios, empezando por la base radioeléctrica, todos los fundamentos de la tecnología RFID y por último describiendo los modelos empíricos usados. Por último se presenta el estudio radioeléctrico, comparando resultados teóricos obtenidos empíricamente y con modelo de trazado de rayos con medidas experimentales en diversos entornos, uno de ellos logístico. Además se evalúa la posibilidad de implantación de un sistema RFID real en este último entorno. De todo este proceso se obtienen muchas conclusiones interesantes.
Open Access
Characterization of wireless channel impact on wireless sensor network performance in public transportation buses
(IEEE, 2015) Azpilicueta Fernández de las Heras, Leyre; López Iturri, Peio; Aguirre Gallego, Erik; Astrain Escola, José Javier; Villadangos Alonso, Jesús; Zubiri Segura, Cristóbal; Falcone Lanas, Francisco; Ingeniería Eléctrica y Electrónica; Ingeniería Matemática e Informática; Ingeniaritza Elektrikoa eta Elektronikoa; Matematika eta Informatika Ingeniaritza
Wireless communications systems are growing rapidly during the last two decades and they are gaining a significant role for multiple communication tasks within public transportation buses. In this work, the impact of topology and morphology of different types of urban buses is analyzed with the aid of an in-house developed 3D Ray Launching code and compared with on-board measurements of a deployed Wireless Sensor Network. The presence of human beings has been taken into account, showing a significant influence in the signal attenuation in the case of considering persons. In addition, the statistical analysis of simulation results considering both large and small-scale fading has been performed, providing good agreement with statistics for typical indoor environments. In addition, a Wireless Sensor Network has been programmed and deployed within the buses in order to analyze topological impact with overall system performance, with the aim of minimizing the energy consumption as well as non-desired interference levels. The use of deterministic techniques destined to consider the inherent complexity of the buses can aid in wireless system planning in order to minimize power consumption and increase overall system capacity.
Open Access
Implementation of context aware e-health environments based on social sensor networks
(MDPI, 2016) Aguirre Gallego, Erik; Led Ramos, Santiago; López Iturri, Peio; Azpilicueta Fernández de las Heras, Leyre; Serrano Arriezu, Luis Javier; Falcone Lanas, Francisco; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa; Gobierno de Navarra / Nafarroako Gobernua
In this work, context aware scenarios applied to e-Health and m-Health in the framework of typical households (urban and rural) by means of deploying Social Sensors will be described. Interaction with end-users and social/medical staff is achieved using a multi-signal input/output device, capable of sensing and transmitting environmental, biomedical or activity signals and information with the aid of a combined Bluetooth and Mobile system platform. The devices, which play the role of Social Sensors, are implemented and tested in order to guarantee adequate service levels in terms of multiple signal processing tasks as well as robustness in relation with the use wireless transceivers and channel variability. Initial tests within a Living Lab environment have been performed in order to validate overall system operation. The results obtained show good acceptance of the proposed system both by end users as well as by medical and social staff, increasing interaction, reducing overall response time and social inclusion levels, with a compact and moderate cost solution that can readily be largely deployed.
Open Access
Analysis and description of HOLTIN service provision for AECG monitoring in complex indoor environments
(MDPI, 2013) Led Ramos, Santiago; Azpilicueta Fernández de las Heras, Leyre; Aguirre Gallego, Erik; Martínez de Espronceda Cámara, Miguel; Serrano Arriezu, Luis Javier; Falcone Lanas, Francisco; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
In this work, a novel ambulatory ECG monitoring device developed in-house called HOLTIN is analyzed when operating in complex indoor scenarios. The HOLTIN system is described, from the technological platform level to its functional model. In addition, by using in-house 3D ray launching simulation code, the wireless channel behavior, which enables ubiquitous operation, is performed. The effect of human body presence is taken into account by a novel simplified model embedded within the 3D Ray Launching code. Simulation as well as measurement results are presented, showing good agreement. These results may aid in the adequate deployment of this novel device to automate conventional medical processes, increasing the coverage radius and optimizing energy consumption.
Open Access
Implementation and analysis of a wireless sensor network-based pet location monitoring system for domestic scenarios
(MDPI, 2016) Aguirre Gallego, Erik; López Iturri, Peio; Azpilicueta Fernández de las Heras, Leyre; Astrain Escola, José Javier; Villadangos Alonso, Jesús; Santesteban Martínez de Morentin, Daniel; Falcone Lanas, Francisco; Ingeniaritza Elektrikoa eta Elektronikoa; Institute for Advanced Materials and Mathematics - INAMAT2; Ingeniería Eléctrica y Electrónica
The flexibility of new age wireless networks and the variety of sensors to measure a high number of variables, lead to new scenarios where anything can be monitored by small electronic devices, thereby implementing Wireless Sensor Networks (WSN). Thanks to ZigBee, RFID or WiFi networks the precise location of humans or animals as well as some biological parameters can be known in real-time. However, since wireless sensors must be attached to biological tissues and they are highly dispersive, propagation of electromagnetic waves must be studied to deploy an efficient and well-working network. The main goal of this work is to study the influence of wireless channel limitations in the operation of a specific pet monitoring system, validated at physical channel as well as at functional level. In this sense, radio wave propagation produced by ZigBee devices operating at the ISM 2.4 GHz band is studied through an in-house developed 3D Ray Launching simulation tool, in order to analyze coverage/capacity relations for the optimal system selection as well as deployment strategy in terms of number of transceivers and location. Furthermore, a simplified dog model is developed for simulation code, considering not only its morphology but also its dielectric properties. Relevant wireless channel information such as power distribution, power delay profile and delay spread graphs are obtained providing an extensive wireless channel analysis. A functional dog monitoring system is presented, operating over the implemented ZigBee network and providing real time information to Android based devices. The proposed system can be scaled in order to consider different types of domestic pets as well as new user based functionalities.
Open Access
Dosimetric study of the radiolectric influence of humans into complex environments through determistic simulations and the implementation of a simplified model
(2014) Aguirre Gallego, Erik; Falcone Lanas, Francisco; Serrano Arriezu, Luis Javier; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
The research presented in this thesis falls under the framework of dosimetry and deterministic estimations. A dosimetric study is carried out with the aid of a 3D Ray Launching simulation technique, by means of an in-house developed code at UPNA. Dosimetry is defined as the calculation of the absorbed dose when a tissue is exposed to electromagnetic radiation, in this case, non-ionizing radiation. It has reached a great importance since a part of the society starts to show concern about the exposure of people to artificial exposures caused by mobile phones or Wi-Fi networks. In fact, some entities (administrations and health bodies) are involved in the regulation and the release of guidelines about this subject. The objective of this thesis is to study dosimetry through 3D Ray Launching simulation technique, calibrating it by the implementation of several scenarios where the simulation tool is tested throughout the comparison of theoretical and measurement results. A simplified human body has been also developed with the aim of employing it in different scenarios, performing dosimetric estimations and providing insight on its influence in the electromagnetic power distribution inside an indoor scenario. Finally, obtained results are compared with different guideline thresholds giving an idea of the compliance of the law when usual wireless communication systems are emitting.
Open Access
Estimation of radiofrequency power leakage from microwave ovens for dosimetric assessment at nonionizing radiation exposure levels
(Hindawi, 2015) López Iturri, Peio; Miguel Bilbao, Silvia de; Aguirre Gallego, Erik; Azpilicueta Fernández de las Heras, Leyre; Falcone Lanas, Francisco; Ramos González, Victoria; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
The electromagnetic field leakage levels of nonionizing radiation from a microwave oven have been estimated within a complex indoor scenario. By employing a hybrid simulation technique, based on coupling full wave simulation with an in-house developed deterministic 3D ray launching code, estimations of the observed electric field values can be obtained for the complete indoor scenario. The microwave oven can be modeled as a time- and frequency-dependent radiating source, in which leakage, basically from the microwave oven door, is propagated along the complete indoor scenario interacting with all of the elements present in it. Thismethod can be of aid in order to assess the impact of such devices on expected exposure levels, allowing adequate minimization strategies such as optimal location to be applied.