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O FAQtos está em curso no INOV-INESC, tendo como objectivo disponibilizar publicamente informação relevante sobre radiação electromagnética em comunicações móveis (...)

 

Exposição à Radiação Proveniente de Antenas de Terminais Móveis



Título An Automated SAR Measurement System for Compliance Testing of Personal Wireless Devices
Resumo An automated specific absorption rate (SAR) measurement system has been developed for compliance testing of personal wireless devices. Unlike other systems, this system uses a model with a lossy ear-shaped protrusion and the accuracy of this experimental setup has been checked by comparing the peak 1-g SAR’s for ten cellular telephones, five each at 835 and 1900 MHz, with the results obtained using a 15-tissue anatomically based model with the finite-difference time-domain (FDTD) numerical electromagnetic technique. The SAR measurement system uses a three-dimensional (3-D) stepper motor to move a Narda Model 8021 E-field probe to measure the SAR distribution inside a headshaped tissue-simulant phantom near the radiating device. The head and neck part of the model with an ear-shaped protrusion of 3 mm thickness is made of a lossy outer shell of 5–7 mm thickness of epoxy laced with KCl solution. The phantom is filled with appropriate frequency-specific fluids with measured electrical properties (dielectric constant and conductivity) that are close to the average for gray and white matters of the brain at the center frequencies of interest (835 and 1900 MHz). The implantable E-field probe is calibrated using the FDTD calculated SAR variations for a slab model at two commonly used frequencies, 835 and 1900 MHz and is checked to have good isotropic characteristics (+/- 0.23 dB) and a wide dynamic range (0.01–10 W/kg). The system is validated using a 223 mm diameter sphere model. Peak 1-g SAR’s for ten telephones using different antennas are within +/-1 dB of those obtained using the FDTD numerical method for the anatomical model of the head and neck region.
Fonte IEEE Transaction on Electromagnetic Compatibility
Origem Internacional
Autor/Editor Qishan Yu, Om P. Gandhi, Magnus Aronsson, and Ding Wu
Disponibilidade Disponível por encomenda
Link ieeexplore.ieee.org
Referência vol. 41, no. 3, pp. 234-245
Data Agosto 1999
Título Automated E-field Scanning System for Dosimetric Assessments
Resumo The interest in accurate dosimetric measurements inside phantoms that simulate biological bodies has burgeoned since several regulatory commissions began calling for or recommending the testing for compliance with safety standards of low power devices. This paper presents a newly developed, robot-based system that allows automated E-field scanning in tissue simulating solutions. The distinguishing characteristics of the system are its high sensitivity and its broad dynamic range (1 uW/g to 100 mW/g) over the entire frequency range (10 MHz to over 3 GHz) used for mobile communications. The reproducibility of the dosimetric evaluations has been shown to be considerably better than +/- 5%. This has been accomplished by the use of an improved isotropic E-field probe connected to amplifiers with extremely low noise and drift characteristics in conjunction with digital processing of data. Special emphazis has been placed on system reliability, user-friendliness and graphic visualization of data.
Fonte IEEE Transactions on Microwave Theory and Techniques
Origem Internacional
Autor/Editor Thomas Schmid, Oliver Egger, Niels Kuster
Disponibilidade Disponível por encomenda
Link ieeexplore.ieee.org
Referência vol. 44, no. 1, pp. 105-113
Data Janeiro 1996
Título Electromagnetic Energy Exposure of Simulated Users of Portable Cellular Telephones
Resumo This paper describes a method to quantify the RF exposure of the users of portable cellular phones in terms of Specific Absorption Rate (SAR). The method involves a robotic system to accurately position an isotropic E-field probe within equivalent biological tissue. The user of cellular phones is simulated by a simple human model (a phantom) consisting of a thin shell of fiberglass filled with a liquid having the complex dielectric constant of human brain tissue. The paper presents the results of the dosimetric assays conducted using current and previous models of cellular telephones. The peak SAR values detected using the measurement method described herein are below the limits recommended by the National Council for Radiation Protection and Measurements (NCRP) Report 86 for the protection of humans exposed to RF electromagnetic energy.
Fonte IEEE Transactions on Vehicular Technology
Origem Internacional
Autor/Editor Quirino Balzano, Oscar Garay, Thomas J. Manning
Disponibilidade Disponível por encomenda
Link ieeexplore.ieee.org
Referência vol. 44, no. 3, pp. 309-403
Data Agosto 1995
Título Guide to the Expression of Uncertainty in Measurements
Resumo When reporting the result of a measurement of a physical quantity, some quantitative indication of the result has to be given to assess its reliability and to allow comparisons to be made. The Guide to the expression of uncertainty in measurement establishes general rules for evaluating and expressing uncertainty in measurement that can be followed at many levels of accuracy and in many fields.
Fonte International Electrotechnical Commission (IEC) / International Organization for Standardization (isso)
Origem Internacional
Autor/Editor ISO/IEC
Disponibilidade Disponível por encomenda
Link iso.org
Referência ISO/IEC Guide 98-3:2008
Data Outubro 2008
Título Human Exposure to Radio Frequency and Microwave Radiation from Portable and Mobile Telephones and Other Wireless Communication Devices
Resumo The Institute of Electrical and Electronics Engineers (IEEE) Committee on Man and Radiation (COMAR) recognises that there is public concern about the safety of exposure to the radio frequency (RF) and microwave (MW) fields from hand-held, portable, and mobile cellular telephones. This report addresses the concerns that have been expressed by some members of the public about the safety of exposure to RF radiation from handheld communications devices, with particular reference to cellular telephone handsets. It gives information about RF Safety Standards and Guidelines, Exposures Produced by Cellular Telephones, Interference to Medical Devices. Some conclusions are drawn.
Fonte Institute of Electrical and Electronics Engineers (IEEE) Committee on Man and Radiation (COMAR)
Origem Estados Unidos da América
Autor/Editor IEEE COMAR
Disponibilidade Disponível online
Link Documento online
Referência
Data Setembro 2000
Título Human exposure to radio frequency fields from hand-held and body-mounted wireless communication devices - Human models, instrumentation, and procedures - Part 1: Procedure to determine the specific absorption rate (SAR) for hand-held devices used in close proximity to the ear (frequency range of 300 MHz to 3 GHz)
Resumo This basic standard applies to any electromagnetic field (EM) transmitting devices to be used with the radiating part of the equipment in close proximity to the human ear including mobile phones, cordless phones, etc. The frequency range is 300 MHz to 3 GHz. The objective of the standard is to specify the method for demonstration of compliance with the specific absorption rate (SAR) limits for such equipment.
Fonte European Committee for Electrotechnical Standardization (CENELEC)
Origem Internacional
Autor/Editor Technical Committee 106X
Disponibilidade Disponível por encomenda
Link cenelec.eu
Referência EN 62209-1:2006
Data Março 2007
Título Human exposure to radio frequency fields from hand-held and body-mounted wireless communication devices - Human models, instrumentation, and procedures - Part 1: Procedure to determine the specific absorption rate (SAR) for hand-held devices used in close proximity to the ear (frequency range of 300 MHz to 3 GHz)
Resumo This basic standard applies to any electromagnetic field (EM) transmitting devices to be used with the radiating part of the equipment in close proximity to the human ear including mobile phones, cordless phones, etc. The frequency range is 300 MHz to 3 GHz. The objective of the standard is to specify the method for demonstration of compliance with the specific absorption rate (SAR) limits for such equipment.
Fonte European Committee for Electrotechnical Standardization (CENELEC)
Origem Internacional
Autor/Editor Technical Committee 106X
Disponibilidade Disponível por encomenda
Link cenelec.eu
Referência EN 62209-1:2006
Data Julho 2001
Título IEEE Recommended Practice for Determining the Peak Spatial-Average Specific Absorption Rate (SAR) in the Human Head from Wireless Communications Devices: Measurement Techniques
Resumo IEEE Std 1528-2003 specifies protocols and test procedures for the measurement of the peak spatial-average SAR induced inside a simplified model of the head of users of certain handheld radio transceivers. These transceivers are intended to be used for personal wireless communications services, operate in the 300 MHz-3 GHz frequency range, and are intended to be operated while held against the ear. The results obtained by following the protocols specified in this recommended practice represent a conservative estimate of the peak spatial-average SAR induced in the head of a significant majority of persons, subject to measurement and other uncertainties that are defined in this standard. The results are representative of those expected during conditions of normal use of a handheld wireless device. It is not the intent of this recommended practice to provide a result representative of the absolute maximum SAR value possible under every conceivable combination of head size, head shape, handset orientation, and spacing relative to the head. The measurement of SAR induced in the external tissues of the head, e.g., the external ear (pinna), is not addressed in this standard. The following items are described in detail: measurement concepts, measurement techniques, instruments, calibration techniques, simulated-tissue (phantom) models, including homogeneous anatomical models of the human head and simple phantoms for validation of the SAR measurement system, and the limitations of these systems when used for measuring the spatial-peak mass-averaged SAR. Procedures for calibrating electric field (E-field) probes used for SAR measurements and assessing the SAR measurement and system uncertainties are provided in the annexes. This recommended practice is intended primarily for use by engineers and other specialists who are familiar with electromagnetic (EM) theory and measurement techniques. This standard does not recommend specific SAR limit values since these are found in other documents. The benefits to the users include standardized and accepted protocols, validation techniques, and means for estimating the overall uncertainty in order to produce valid and repeatable data.
Fonte Institute of Electrical and Electronics Engineers (IEEE) Standards Coordinating Committee 34 (SCC 34)
Origem Estados Unidos da América
Autor/Editor IEEE - SCC 34
Disponibilidade Disponível por encomenda
Link ieeexplore.ieee.org
Referência IEEE Std. 1528-2003
Data Dezembro 2003
Título IEEE Recommended Practice for Determining the Peak Spatial-Average Specific Absorption Rate (SAR) in the Human Head from Wireless Communications Devices: Measurement Techniques
Resumo IEEE Std 1528-2003 specifies protocols and test procedures for the measurement of the peak spatial-average SAR induced inside a simplified model of the head of users of certain handheld radio transceivers. These transceivers are intended to be used for personal wireless communications services, operate in the 300 MHz-3 GHz frequency range, and are intended to be operated while held against the ear. The results obtained by following the protocols specified in this recommended practice represent a conservative estimate of the peak spatial-average SAR induced in the head of a significant majority of persons, subject to measurement and other uncertainties that are defined in this standard. The results are representative of those expected during conditions of normal use of a handheld wireless device. It is not the intent of this recommended practice to provide a result representative of the absolute maximum SAR value possible under every conceivable combination of head size, head shape, handset orientation, and spacing relative to the head. The measurement of SAR induced in the external tissues of the head, e.g., the external ear (pinna), is not addressed in this standard. The following items are described in detail: measurement concepts, measurement techniques, instruments, calibration techniques, simulated-tissue (phantom) models, including homogeneous anatomical models of the human head and simple phantoms for validation of the SAR measurement system, and the limitations of these systems when used for measuring the spatial-peak mass-averaged SAR. Procedures for calibrating electric field (E-field) probes used for SAR measurements and assessing the SAR measurement and system uncertainties are provided in the annexes. This recommended practice is intended primarily for use by engineers and other specialists who are familiar with electromagnetic (EM) theory and measurement techniques. This standard does not recommend specific SAR limit values since these are found in other documents. The benefits to the users include standardized and accepted protocols, validation techniques, and means for estimating the overall uncertainty in order to produce valid and repeatable data.
Fonte Institute of Electrical and Electronics Engineers (IEEE) Standards Coordinating Committee 34 (SCC 34)
Origem Estados Unidos da América
Autor/Editor IEEE - SCC 34
Disponibilidade Disponível por encomenda
Link ieeexplore.ieee.org
Referência IEEE Std. 1528-2003
Data Dezembro 2003
Título Influência Mútua entre o Telefone Celular e a Cabeça Humana
Resumo Esta comunicação aborda o problema da influência mútua entre a antena de um telefone móvel e a cabeça humana. Depois de uma breve referência aos métodos usados para a obtenção de valores para as várias grandezas que caracterizam o problema, discute-se as duas perspetivas dessa influência, apresentando-se alguns resultados. Referem-se ainda os limites máximos permitidos para as potências emitidas pelos telefones, de acordo com os organismos internacionais.
Fonte Actas das III Jornadas Portuguesas de Protecção contra Radiações
Origem Portugal
Autor/Editor Luis M. Correia
Disponibilidade Sociedade Portuguesa de Protecção contra Radiações, Lisboa, Portugal
Referência
Data Março 1996
Título OET Bulletin 65, Supplement C - Evaluating Compliance with FCC Guidelines for Human Exposure to Radiofrequency Electromagnetic Fields, Additional Information for Evaluating Compliance of Mobile and Portable Devices with FCC Limits for Human Exposure
Resumo In August, 1996, the Commission adopted a Report and Order in ET Docket 93-62 amending its rules for evaluating the environmental effects of radiofrequency (RF) electromagnetic fields. Specifically, the Commission adopted new guidelines and procedures for evaluating human exposure to RF emissions from FCC-regulated transmitters and facilities. As a part of this proceeding, new limits were adopted for human exposure to RF emissions from certain mobile and portable devices. Two subsequent FCC Orders were issued to refine and clarify the decisions adopted in the original Report and Order. A revised version of OET Bulletin 65, "Evaluating Compliance with FCC Guidelines for Human Exposure to Radiofrequency Electromagnetic Fields" was also issued. One of the areas discussed in Bulletin 65 is compliance with the limits adopted by the Commission for safe exposure to RF emissions due to mobile and portable devices such as non-fixed wireless transmitters and hand-held cellular telephones. The first edition of Supplement C (97-01) was released in 1997. The purpose of this revised supplement is to provide parties filing applications for equipment authorization with guidance on complying with the latest requirements using up-to-date test procedures. This supplement is not intended, however, to establish mandatory procedures, and other methods and procedures may be acceptable if based on sound engineering practice.
Fonte Federal Communications Commission (FCC)
Origem Estados Unidos da América
Autor/Editor David L. Means, Kwok W. Chan
Disponibilidade Disponível online
Link fcc.gov
Referência OET Bulletin 65, Supplement C
Data Junho 2001
Título OET Bulletin 65, Supplement C - Evaluating Compliance with FCC Guidelines for Human Exposure to Radiofrequency Electromagnetic Fields, Additional Information for Evaluating Compliance of Mobile and Portable Devices with FCC Limits for Human Exposure
Resumo In August, 1996, the Commission adopted a Report and Order in ET Docket 93-62 amending its rules for evaluating the environmental effects of radiofrequency (RF) electromagnetic fields. Specifically, the Commission adopted new guidelines and procedures for evaluating human exposure to RF emissions from FCC-regulated transmitters and facilities. As a part of this proceeding, new limits were adopted for human exposure to RF emissions from certain mobile and portable devices. Two subsequent FCC Orders were issued to refine and clarify the decisions adopted in the original Report and Order. A revised version of OET Bulletin 65, "Evaluating Compliance with FCC Guidelines for Human Exposure to Radiofrequency Electromagnetic Fields" was also issued. One of the areas discussed in Bulletin 65 is compliance with the limits adopted by the Commission for safe exposure to RF emissions due to mobile and portable devices such as non-fixed wireless transmitters and hand-held cellular telephones. The first edition of Supplement C (97-01) was released in 1997. The purpose of this revised supplement is to provide parties filing applications for equipment authorization with guidance on complying with the latest requirements using up-to-date test procedures. This supplement is not intended, however, to establish mandatory procedures, and other methods and procedures may be acceptable if based on sound engineering practice.
Fonte Federal Communications Commission (FCC)
Origem Estados Unidos da América
Autor/Editor David L. Means, Kwok W. Chan
Disponibilidade Disponível online
Link fcc.gov
Referência OET Bulletin 65, Supplement C
Data Junho 2001
Título Product standard to demonstrate the compliance of mobile phones with the basic restrictions related to human exposure to electromagnetic fields (300 MHz - 3 GHz)
Resumo The standard, EN 50360 - product standard to demonstrate the compliance of mobile phones with the basic restrictions related to human exposure to electromagnetic fields (300 MHz - 3 GHz), sets down limits recommended by the Council in a Council Recommendation of 12 July 1999 on the limitation of exposure of the general public to electromagnetic fields (0 Hz to 300 GHz).
Fonte European Committee for Electrotechnical Standardization (CENELEC)
Origem Internacional
Autor/Editor CENELEC
Disponibilidade Disponível por encomenda
Link cenelec.eu
Referência BS EN 50360:2001+A1:2012
Data Abril 2012
Título SAR Generated by Commercial Cellular Phones — Phone Modeling, Head Modeling, and Measurements
Resumo This paper presents the computation of the specific absorption rate (SAR) generated by cellular phones inside an anatomical model of a head. Four models of commercially available phones have been considered working at 900- and 1800-MHz bands (global system for mobile communication system). The phones have been modeled by using a computer-aided design representation obtained through the reverse engineering technique. Both SAR distributions and SAR averaged values have been computed inside the anatomical model of a head, by using the finite-difference time-domain method. Computations have been experimentally validated through measurements performed inside anthropomorphic phantoms irradiated by a dipole and cellular phones.
Fonte IEEE Transactions on Microwave Theory and Techniques
Origem Internacional
Autor/Editor Andrea Schiavoni, Paola Bertotto, Gabriella Richiardi, Paolo Bielli
Disponibilidade Disponível por encomenda
Link ieeexplore.ieee.org
Referência vol. 48, no. 11, pp. 2064-2079
Data Novembro 2000
Título The Dependence of Electromagnetic Energy Absorption Upon Human Head Tissue Composition in the Frequency Range of 300-3000 MHz
Resumo The requirements for testing compliance of cellular phones with electromagnetic safety limits demand evaluation of the maximum exposure that may occur in the user group under normal operational conditions. Under these conditions, the tissues of the ear region are most exposed, the tissue composition of which is complex and varies considerably from user to user. The objective of this paper is to derive head tissue equivalent dielectric parameters that enable the utilization of one generic homogeneous head for testing compliance for the entire user group, i.e., granting no underestimation, but also not greatly overestimating the actual maximum user exposure. As a primary study, a simple analytical model of an infinite half-space layered tissue model exposed to a plane wave was utilized to investigate the impact of impedancematching standing waves, etc. on the spatial-peak specific absorption rate. The tissue layers were varied in composition and thickness, representing the anatomical variation of the exposed head region covering the user group including adults and children ( 10% to 90% percentile). Based on the worst-case tissue layer compositions with respect to absorption at each frequency, head tissue equivalent dielectric parameters for homogeneous modeling were derived, which result in the same spatial-peak absorption. The validity of this approach for near-field exposures was demonstrated by replacing the plane wave by different near-field sources (dipoles and generic phones) and the layered structure with magnetic-resonance-image-based nonhomogeneous human head models.
Fonte IEEE Transactions on Microwave Theory and Techniques
Origem Internacional
Autor/Editor Antonios Drossos, Veli Santomaa, Niels Kuster
Disponibilidade Disponível por encomenda
Link ieeexplore.ieee.org
Referência vol. 48, no. 11, pp. 1988-1995
Data Novembro 2000

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