5G spatial modeling of personal RF-EMF assessment within aircrafts cabin environments

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.This work was supported by the Ministerio de Ciencia, Innovación y Universidades, Gobierno de España (MCIU/AEI/FEDER, UE) under Project RTI2018-095499-B-C31

Towards environmental RF-EMF assessment of mmwave high-node density complex heterogeneous environments

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.Project RTI2018-095499-B-C31 was funded by the Ministerio de Ciencia, Innovación y Universidades, Gobierno de España (MCIU/AEI/FEDER, UE). This project received funding from Universidad Carlos III de Madrid and the European Union's Horizon 2020 research and innovation programme under Marie Sklodowska-Curie Grant 801538

Monitoring of electromagnetic field exposure in an international context

Objectives: Electromagnetic field exposure to general people is a public health concern and a topic of debate globally. Electromagnetic field is non-ionizing part of electromagnetic spectrum that can further be divided into extremely low frequency (0- 10 MHz) EMF and radiofrequency (10-300 MHz) EMF based on frequency and corresponding wavelength. Both of these components are of a topic of public debate and a subject of on-going research. The most common sources of extremely low frequency fields are alternating current carried in wiring, household appliances, power lines, electrical wiring, and electrical equipment. Some common sources of radiofrequency fields are mobile phone handsets and mobile phone base stations. Hence the main goals of this thesis were to propose a validated 3D computer model for extremely low frequency magnetic field exposure assessment from overhead powerlines and to develop a novel method of assessing radiofrequency field exposure in different microenvironments. More specifically, this thesis was planned with four different objectives as below: To systematically review the radiofrequency electromagnetic field exposure situation in the European countries based on peer-reviewed articles on spot measurements, personal measurement with trained researchers, and personal measurement with volunteers studies. To test the suitability of microenvironmental measurement surveys with portable exposimeters for monitoring of radiofrequency electromagnetic field levels in various everyday microenvironments in Switzerland. To apply already tested radiofrequency electromagnetic field monitoring protocol to monitor radiofrequency electromagnetic field exposure from Switzerland to international microenvironments of Ethiopia, Nepal, South Africa, Australia and the United States of America To validate a 3D computer model, developed for the calculation of the absolute value of magnetic flux density from an overhead power line, with a 6 measurement campaign conducted every two months for a year time. Methods: For the systematic review for radiofrequency electromagnetic field exposure in European countries, we systematically searched the ISI Web of Science for relevant literature published between 1st January, 2000 and 30th April, 2015 that assessed RF-EMF exposure levels by any of the methods; spot measurements, personal measurement with trained researchers and personal measurement with volunteers. For the non-ionizing radiation monitoring in Switzerland, we used ExpoM-RF device mounted on a backpack to assess radiofrequency electromagnetic field by walking through 51 different outdoor microenvironments from 20 different municipalities in Switzerland. Measurements were conducted between 25th March and 11th July 2014. The non-ionizing radiation monitoring in international microenvironments used the tested protocol from non-ionizing radiation monitoring in Switzerland. The measurements in international microenvironments were taken using two different kinds of portable RF meter called “ExpoM-RF” and “EME Spy 201”. The measurements were conducted either by walking (Switzerland and Nepal) or driving a car with ExpoM-RF device mounted on its roof (Ethiopia, South Africa, Australia, and the United States of America) or mixed walking and driving (Ethiopia, South Africa, Australia). We selected 15 different microenvironments from Switzerland, 18 microenvironments from Ethiopia, 12 microenvironments from Nepal, and 17 microenvironments from South Africa, 24 microenvironments from Australia and 8 microenvironments from the United States of America. Each of the selected microenvironments was measure twice: between 10 March and 14 April 2017. For the powerline validation study, six measurements were taken every two month between January 2015 and December 2015 from two different locations on two different power lines in order to describe variation of extremely low frequency magnetic field exposure by different seasons of the year. The measurements were taken from the selected power lines for at least 48 hours from each line on each measurement day. The measurements were taken using EMDEX II, temperature logger, and ESTEC device. Results: The systematic review yielded twenty one published studies that met our eligibility criteria of which 10 were spot measurements studies, 5 were personal measurement studies with trained researchers (microenvironmental), 5 were personal measurement studies with volunteers and 1 was a mixed methods study combining data collected by volunteers and trained researchers. The mean total RF-EMF exposure for spot measurements in European “Homes” and “Outdoor” microenvironments was 0.29 V/m and 0.54 V/m respectively. Among all European microenvironments in “Transportation”, the highest mean total RF-EMF 1.96 V/m was found in trains of Belgium during 2007 where more than 95% of exposure was contributed by uplink. The non-ionizing radiation monitoring in Switzerland found mean RF-EMF exposure of 0.53 V/m in industrial zones, 0.47 V/m in city centers, 0.32 V/m in central residential areas, 0.25 V/m non-central residential areas, 0.23 V/m in rural centers and rural residential areas, 0.69 V/m in trams, 0.46 V/m in trains and 0.39 V/m in buses. Temporal correlation between first and second measurement of each path was high: 0.83 for total RF-EMF, 0.83 for all five mobile phone downlink bands combined, 0.54 for all five uplink bands combined and 0.79 for broadcasting. The non-ionizing radiation monitoring internationally found mean RF-EMF exposure in all 5 countries varied between 0.94 V/m and 0.05 V/m. Mean total RF-EMF exposure was highest in Australia (0.94 V/m city centers) and lowest in South Africa (0.36 V/m in rural centers and rural residential areas). For outdoor areas major exposure contribution was from mobile phone base station. The mobile phone base stations contributed more than 65% in all measured microenvironments across the 5 countries. The two components of the powerline validation study: feasibility study by a computer model and its validation by field measurement of extremely low frequency magnetic field found the estimated precision of the results to be of the order of 10 % to 25 %, and this large degree precision may be due to errors in the coordinates and heights. The both components of the study helped in identifying the input data necessary for large-scale modeling of magnetic fields from high-voltage power lines and how long-term temporal averages of the field can be computed. Conclusion: The systematic review of radiofrequency electromagnetic field concluded that typical radiofrequency electromagnetic field exposure levels are substantially below regulatory limits. The non-ionizing radiation monitoring in Switzerland demonstrated that microenvironmental surveys using a portable device yields highly repeatable measurements, which allows monitoring time trends of RF-EMF exposure over an extended time period of several years and to compare exposure levels between different types of microenvironments. The non-ionizing radiation monitoring in international microenvironments further support the results from pilot study in Switzerland. The powerline validation study concluded the model agrees well with the measurement values, with average offsets in the range of a few percent. We also found that the precision of the results corresponds to the precision estimated during the pilot study

Electromagnetic Assessment of UHF-RFID Devices in Healthcare Environment

In this work, the evaluation of electromagnetic effect of Ultra High Frequency Radio Frequency Identification (UHF-RFID) passive tags used in the healthcare environment is presented. In order to evaluate exposure levels caused by EM field (865–868 MHz) of UHF-RFID readers, EM measurements in an anechoic chamber and in a real medical environment (Hospital Universitario de Canarias), as well as simulations by 3D Ray Launching algorithm, and of biophysical exposure effects in human models are presented. The results obtained show that the EM exposure is localized, in close vicinity of RFID reader and inversely proportional to its reading range. The EM exposure levels detected are sufficient to cause EM immunity effects in electronic devices (malfunctions in medical equipment or implants). Moreover, more than negligible direct effects in humans (exceeding relevant SAR values) were found only next to the reader, up to approximately 30% of the reading range. As a consequence, the EM risk could be firstly evaluated based on RFID parameters, but should include an in situ exposure assessment. It requires attention and additional studies, as increased applications of monitoring systems are observed in the healthcare sector—specifically when any system is located close to the workplace that is permanently occupied.This work was supported by Instituto de Salud Carlos III project “Electromagnetic “Characterization in Smart Environments of Healthcare, and their involvement in Personal, Occupational, and Environmental Health” (PI14CIII/00056) https://portalfis.isciii.es/es/Paginas/DetalleProyecto. aspx?idProyecto=PI14CIII%2f00056 (accessed on 24 July 2022), and project “ (PI19CIII/00033) TMPY 508/19 “ Metrics development for electromagnetic safety assessment in healthcare centers in the context of 5G“ https://portalfis.isciii.es/es/Paginas/DetalleProyecto.aspx?idProyecto=PI19 CIII%2f00033, (accessed on 24 July 2022) from Sub-Directorate-General for Research Assessment and Promotion. The results of a research task (II.PB.15) carried out within the National Programme “Improvement of safety and working conditions” partly supported in Poland in 2020-2022-within the scope of research and development-by the National Centre for Research and Development were also included.S

Electromagnetic assessment of UHF-RFID devices in healthcare environment

In this work, the evaluation of electromagnetic effect of Ultra High Frequency Radio Frequency Identification (UHF-RFID) passive tags used in the healthcare environment is presented. In order to evaluate exposure levels caused by EM field (865–868 MHz) of UHF-RFID readers, EM measurements in an anechoic chamber and in a real medical environment (Hospital Universitario de Canarias), as well as simulations by 3D Ray Launching algorithm, and of biophysical exposure effects in human models are presented. The results obtained show that the EM exposure is localized, in close vicinity of RFID reader and inversely proportional to its reading range. The EM exposure levels detected are sufficient to cause EM immunity effects in electronic devices (malfunctions in medical equipment or implants). Moreover, more than negligible direct effects in humans (exceeding relevant SAR values) were found only next to the reader, up to approximately 30% of the reading range. As a consequence, the EM risk could be firstly evaluated based on RFID parameters, but should include an in situ exposure assessment. It requires attention and additional studies, as increased applications of monitoring systems are observed in the healthcare sector—specifically when any system is located close to the workplace that is permanently occupied.This work was supported by Instituto de Salud Carlos III project “Electromagnetic Characterization in Smart Environments of Healthcare, and their involvement in Personal, Occupational, and Environmental Health” (PI14CIII/00056), and project (PI19CIII/00033) TMPY 508/19 “Metrics development for electromagnetic safety assessment in healthcare centers in the context of 5G“ from Sub-Directorate-General for Research Assessment and Promotion. The results of a research task (II.PB.15) carried out within the National Programme “Improvement of safety and working conditions” partly supported in Poland in 2020–2022—within the scope of research and development—by the National Centre for Research and Development were also included

Estimation of real traffic radiated emissions from electric vehicles in terms of the driving profile using neural networks

The increment of the use of electric vehicles leads to a worry about measuring its principal source of environmental pollution: electromagnetic emissions. Given the complexity of directly measuring vehicular radiated emissions in real traffic, the main contribution of this PhD thesis is to propose an indirect solution to estimate such type of vehicular emissions. Relating the on-road vehicular radiated emissions with the driving profile is a complicated task. This is because it is not possible to directly measure the vehicular radiated interferences in real traffic due to potential interferences from another electromagnetic wave sources. This thesis presents a microscopic artificial intelligence model based on neural networks to estimate real traffic radiated emissions of electric vehicles in terms of the driving dynamics. Instantaneous values of measured speed and calculated acceleration have been used to characterize the driving profile. Experimental electromagnetic interference tests have been carried out with a Vectrix electric motorcycle as well as Twizy electric cars in semi-anechoic chambers. Both the motorcycle and the car have been subjected to different urban and interurban driving profiles. Time Domain measurement methodology of electromagnetic radiated emissions has been adopted in this work to save the overall measurement time. The relationship between the magnetic radiated emissions of the Twizy and the corresponding speed has been very noticeable. Maximum magnetic field levels have been observed during high speed cruising in extra-urban driving and acceleration in urban environments. A comparative study of the prediction performance between various static and dynamic neural models has been introduced. The Multilayer Perceptron feedforward neural network trained with Extreme Learning Machines has achieved the best estimation results of magnetic radiated disturbances as function of instantaneous speed and acceleration. In this way, on-road magnetic radiated interferences from an electric vehicle equipped with a Global Positioning System can be estimated. This research line will allow quantify the pollutant electromagnetic emissions of electric vehicles and study new policies to preserve the environment

Estimation of real traffic radiated emissions from electric vehicles in terms of the driving profile using neural networks

The increment of the use of electric vehicles leads to a worry about measuring its principal source of environmental pollution: electromagnetic emissions. Given the complexity of directly measuring vehicular radiated emissions in real traffic, the main contribution of this PhD thesis is to propose an indirect solution to estimate such type of vehicular emissions. Relating the on-road vehicular radiated emissions with the driving profile is a complicated task. This is because it is not possible to directly measure the vehicular radiated interferences in real traffic due to potential interferences from another electromagnetic wave sources. This thesis presents a microscopic artificial intelligence model based on neural networks to estimate real traffic radiated emissions of electric vehicles in terms of the driving dynamics. Instantaneous values of measured speed and calculated acceleration have been used to characterize the driving profile. Experimental electromagnetic interference tests have been carried out with a Vectrix electric motorcycle as well as Twizy electric cars in semi-anechoic chambers. Both the motorcycle and the car have been subjected to different urban and interurban driving profiles. Time Domain measurement methodology of electromagnetic radiated emissions has been adopted in this work to save the overall measurement time. The relationship between the magnetic radiated emissions of the Twizy and the corresponding speed has been very noticeable. Maximum magnetic field levels have been observed during high speed cruising in extra-urban driving and acceleration in urban environments. A comparative study of the prediction performance between various static and dynamic neural models has been introduced. The Multilayer Perceptron feedforward neural network trained with Extreme Learning Machines has achieved the best estimation results of magnetic radiated disturbances as function of instantaneous speed and acceleration. In this way, on-road magnetic radiated interferences from an electric vehicle equipped with a Global Positioning System can be estimated. This research line will allow quantify the pollutant electromagnetic emissions of electric vehicles and study new policies to preserve the environment

Not in My Neighborhood: A User Equipment Perspective of Cellular Planning Under Restrictive EMF Limits

The installation of base station (BS) sites is regulated by a variety of laws at international, national, and local levels. While international regulations are already severe, the national and local laws applied in many countries and regions follow precautionary principles and enforce electromagnetic field (EMF) constraints that are even more restrictive. This legal environment results in substantial constraints affecting the planning of cellular networks, as requests for new BS site installation are easily denied by national or local authorities. In this paper, we consider the problem of cellular planning under restrictive EMF limits from the user equipment (UE) viewpoint. We focus on outdoor urban areas and first evaluate the impact of the current, non-optimal network planning at the UE side through a quantitative measurement-driven analysis of the quality of service (QoS) observed by users in heterogeneous, large-scale urban scenarios. We then perform a qualitative assessment of the perceived QoS and generated EMF levels at one UE transferring data from/to a BS based on its position with respect to the serving BS. Finally, we run a what-if analysis by comparing the existing planning with the one where new BS sites can be installed, thanks to a relaxation of the restrictive EMF constraints. Our results clearly show that a cellular planning driven by restrictive EMF constraints forces UE to experience large distances from the serving BS, frequent non-line-of-sight conditions, and poor received signal. In turn, this entails a very negative combination of high electric field activity (EFA) levels generated by the UE and low QoS perceived by the user. We show that, by relaxing the restrictive EMF constraints, the problem could be sensibly mitigated with a positive impact on the UE channel conditions and consequently on the perceived QoS and the UE EFA