Numerical Implementation of Representative Mobile Phone Models for Epidemiological Studies

This paper describes an implementation method and the results of numerical mobile phone models representing real phone models that have been released on the Korean market since 2002. The aim is to estimate the electromagnetic absorption in the human brain for casecontrol studies to investigate health risks related to mobile phone use. Specific absorption rate (SAR) compliance test reports about commercial phone models were collected and classified in terms of elements such as the external body shape, the antenna, and the frequency band. The design criteria of a numerical phone model representing each type of phone group are as follows. The outer dimensions of the phone body are equal to the average dimensions of all commercial models with the same shape. The distance and direction of the maximum SAR from the earpiece and the area above –3 dB of the maximum SAR are fitted to achieve the average obtained by measuring the SAR distributions of the corresponding commercial models in a flat phantom. Spatial peak 1-g SAR values in the cheek and tilt positions against the specific anthropomorphic mannequin phantom agree with average data on all of the same type of commercial models. Second criterion was applied to only a few types of models because not many commercial models were available. The results show that, with the exception of one model, the implemented numerical phone models meet criteria within 30%

A novel method to assess human population exposure induced by a wireless cellular network

<p>This paper presents a new metric to evaluate electromagnetic exposure induced by wireless cellular networks. This metric takes into account the exposure induced by base station antennas as well as exposure induced by wireless devices to evaluate average global exposure of the population in a specific geographical area. The paper first explains the concept and gives the formulation of the Exposure Index (EI). Then, the EI computation is illustrated through simple phone call scenarios (indoor office, in train) and a complete macro urban data long-term evolution scenario showing how, based on simulations, radio-planning predictions, realistic population statistics, user traffic data, and specific absorption rate calculations can be combined to assess the index.</p

Power control for WCDMA

This project tries to introduce itself in the physical implementations that make possible the denominated third generation mobile technology. As well as to know the technology kind that makes possible, for example, a video-call in real time. During this project, the different phases passed from the election of WCDMA like the access method for UMTS will appear. Its coexistence with previous network GSM will be analyzed, where the compatibility between systems has been one of the most important aspects in the development of WCDMA, the involved standardization organisms in the process, as well as the different protocols that make the mobile communications within a network UTRAN possible. Special emphasis during the study of the great contribution that has offered WCDMA with respect to the control of power of the existing signals will be made. The future lines that are considered in the present, and other comment that already are in their last phase of development in the field of the mobile technology. UMTS through WCDMA can be summarized like a revolution of the air interface accompanied by a revolution in the network of their architecture

Effect of Magnetic Field From Mobile Phone on Brain

Human exposure to electromagnetic field (EMF) comes from many different sources and occurs in various situations in everyday life. Man-made static fields are mainly found in occupational settings, such as close to magnetic resonance imaging (MRI) scanners, although DC high-voltage overhead transmission lines are being constructed, which are expected to expose larger parts of the population to static electric and magnetic fields.Today, for power regulation most modern electrical equipment uses electronics instead of transformers. Examples include the switched power supplies to laptops, drilling tools, chargers of mobile phones and similar devices. As a consequence, the frequency content of the daily magnetic field exposure has changed mainly by adding odd harmonics (150 Hz, 250 Hz, 750 Hz, etc.). In particular, the third harmonic (150 Hz) has become another dominating frequency in our environment.In particular for brain tissues, the mobile phone used at the ear remains the main source of exposure. However, since the first generation of mobile telephony, the technology aimed at reducing the emitted power of mobile handsets. In particular, for Global System for Mobile communication (GSM) already the introduction of dynamic power control reduced the average output power to about 50% of its rated value during calls, whereas the use of discontinuous transmission during voice calls gave a further 30% reduction in average emitted power. Adaptive power control became faster and more effective in the third-generation (3G) of mobile telephony systems leading to a further reduction (by about two orders of magnitude) in the specific absorption Specific energy Absorption Rate (SAR) compared to GSM phones. In addition, hands-free kits reduce the energy absorbed by the head drastically. Digital Enhanced Cordless Telecommunications (DECT) phones are another source of everyday exposure

Développement d'une méthodologie pour l'évaluation de l'exposition réelle des personnes aux champs électromagnétiques

The work presented in the thesis is directed towards addressing the requirement for determining the radio frequency (RF) exposure due to mobile phones under typical usage/ real-life scenarios and also to develop a method to predict and compare mobile phones for their real-life RF exposure. The mobile phones are characterized for their specific absorption rate (SAR) and for transmit and receive performance given by the over-the-air (OTA) characterization. Using the SAR and the total radiated power (TRP) characterization, an exposure index referred to as the SAROTA index was previously proposed to predict the real-life exposure due to mobile phones which would also serve as a metric to compare individual phones. In order to experimentally determine the real-life RF exposure, various software modified phones (SMP) are utilized for the study. These phones contain an embedded software capable of recording the network parameters. The study is undertaken in the following order: (a) Characterization of the available tools and resources for performing targeted measurements/experiments, (b) identifying the important radio resource parameters and metrics to perform the targeted measurements, (c) investigation of the actual implementation of the power control mechanism in a live network for various received signal level and received quality environments, (d) investigating the correlation of the over-the-air performance of the mobile phones and the extent of actual power control realization, (e) comparing the actual exposure and the real-life exposure as predicted by the SAROTA index. Based on the logistical and technical challenges encountered, the experiments were restricted to indoor environments to enable repeatability. During the first phase of the study, the stability of the indoor environment was evaluated. During the second phase, the influence of hand phantom on the SAR and TRP of the mobile phones and the capability of the SAROTA index to predict the exposure was investigated. Further developing on the insights from the hand phantom experiments, in the third phase, a set of identical software modified phones were externally modified to alter the TRP performance and the methodology to determine the real-life exposure and also verify the capability of the SAROTA index to predict the exposure levels was investigated. The experiments demonstrate that the SAROTA index is capable of predicting the real-life exposure and comparing the mobile phones.Le travail présenté dans cette thèse a pour objectif l’étude des conditions nécessaires pour évaluer l'exposition radio fréquence (RF) due aux téléphones mobiles dans un scenario d’utilisation réelle et le développement d’une méthodologie permettant de prédire et de comparer les téléphones mobiles en fonction de leurs expositions RF réelles. Les téléphones mobiles sont caractérisés par leur débit d'absorption spécifique (DAS) et leur performance en émission et en réception (over-the-air, OTA). En utilisant le DAS et la puissance totale rayonnée (PTR), un indice d'exposition appelée l'indice SAROTA a été proposé précédemment afin de prévoir l'exposition réelle des téléphones mobiles. L’indice SAROTA sert ainsi de métrique permettant de comparer les téléphones mobiles. Afin de déterminer expérimentalement l’exposition réelle aux RF, plusieurs téléphones avec des modifications logicielles permettant d’enregistrer les paramètres du réseau, sont utilisés pour l’étude qui est menée comme suit : (a) caractérisation des outils et des ressources disponibles pour effectuer des mesures ciblées, (b) identification des ressources radio et des paramètres importants pour effectuer ces mesures, (c) étude de la mise en œuvre effective du mécanisme de contrôle de puissance observé dans un réseau mobile réel pour différents niveaux et de qualités du signal reçus, (d) étude de la corrélation entre la performance OTA des téléphones mobiles et l’étendue effective du contrôle de puissance appliquée par le réseau, (e) comparaison entre la valeur réelle de l’exposition et la valeur prédite en utilisant l’indice SAROTA. Comme les défis logistiques et techniques sont plus difficiles à surmonter pour les mesures dans un environnement multi-trajets extérieur, les expériences ont été limitées à des environnements intérieurs pour assurer une meilleure répétabilité des mesures. Lors d’une première phase de l’étude, la stabilité de l’environnement intérieur a été évaluée. Lors d’une deuxième phase, l’influence de la main sur le DAS et la PTR des téléphones mobiles ainsi que sur l’évaluation de l’exposition réelle prédite par l’indice SAROTA a été étudiée. Lors d’une troisième phase, un ensemble de téléphones mobiles identiques ont été modifiés et des mesures effectuées pour vérifier que l’indice SAROTA permet bien de prédire l’exposition réelle des personnes

Power control for WCDMA

This project tries to introduce itself in the physical implementations that make possible the denominated third generation mobile technology. As well as to know the technology kind that makes possible, for example, a video-call in real time. During this project, the different phases passed from the election of WCDMA like the access method for UMTS will appear. Its coexistence with previous network GSM will be analyzed, where the compatibility between systems has been one of the most important aspects in the development of WCDMA, the involved standardization organisms in the process, as well as the different protocols that make the mobile communications within a network UTRAN possible. Special emphasis during the study of the great contribution that has offered WCDMA with respect to the control of power of the existing signals will be made. The future lines that are considered in the present, and other comment that already are in their last phase of development in the field of the mobile technology. UMTS through WCDMA can be summarized like a revolution of the air interface accompanied by a revolution in the network of their architecture

Conduct of a personal radiofrequency electromagnetic field measurement study: proposed study protocol

Background: The development of new wireless communication technologies that emit radio frequency electromagnetic fields (RF-EMF) is ongoing, but little is known about the RF-EMF exposure distribution in the general population. Previous attempts to measure personal exposure to RF-EMF have used different measurement protocols and analysis methods making comparisons between exposure situations across different study populations very difficult. As a result, observed differences in exposure levels between study populations may not reflect real exposure differences but may be in part, or wholly due to methodological differences. Methods: The aim of this paper is to develop a study protocol for future personal RF-EMF exposure studies based on experience drawn from previous research. Using the current knowledge base, we propose procedures for the measurement of personal exposure to RF-EMF, data collection, data management and analysis, and methods for the selection and instruction of study participants. Results: We have identified two basic types of personal RF-EMF measurement studies: population surveys and microenvironmental measurements. In the case of a population survey, the unit of observation is the individual and a randomly selected representative sample of the population is needed to obtain reliable results. For microenvironmental measurements, study participants are selected in order to represent typical behaviours in different microenvironments. These two study types require different methods and procedures. Conclusion: Applying our proposed common core procedures in future personal measurement studies will allow direct comparisons of personal RF-EMF exposures in different populations and study areas

Mobile phone use, behavioural problems and concentration capacity in adolescents : a prospective study

The aim of this study is to prospectively investigate whether exposure to radiofrequency electromagnetic fields (RF-EMF) emitted by mobile phones and other wireless communication devices is related to behavioural problems or concentration capacity in adolescents. The HERMES (Health Effects Related to Mobile phonE use in adolescentS) study sample consisted of 439 Swiss adolescents aged 12-17 years. Behavioural problems were assessed using the Strengths and Difficulties Questionnaire (SDQ), concentration capacity of the adolescents was measured by means of a standardized computerized cognitive test named FAKT. Cross-sectional and longitudinal (1year of follow-up) analyses were performed to investigate possible associations between behavioural problems and concentration capacity and different exposure measures: self-reported and operator-recorded wireless communication device use, cumulative RF-EMF brain and whole body dose and measured personal RF-EMF exposure. In the cross-sectional analyses behavioural problems were associated with several self-reported wireless device use measures but not operator-recorded mobile phone use measures, concentration capacity was associated with several self-reported and operator-recorded exposures. The longitudinal analyses point towards absence of associations. The lack of consistent exposure-response patterns in the longitudinal analyses suggests that behavioural problems and concentration capacity are not affected by the use of wireless communication devices or RF-EMF exposure. Information bias and reverse causality are likely explanations for the observed cross-sectional findings