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Electromagnetic dosimetry for adult and child models within a car: multi-exposure scenarios

Published online by Cambridge University Press:  29 November 2011

Louis-Ray Harris
Affiliation:
University of Technology, Kingston, Jamaica.
Maxim Zhadobov*
Affiliation:
Institute of Electronics and Telecommunications of Rennes (IETR), UMR CNRS 6164, University of Rennes 1, Rennes, France.
Nacer Chahat
Affiliation:
Institute of Electronics and Telecommunications of Rennes (IETR), UMR CNRS 6164, University of Rennes 1, Rennes, France.
Ronan Sauleau
Affiliation:
Institute of Electronics and Telecommunications of Rennes (IETR), UMR CNRS 6164, University of Rennes 1, Rennes, France.
*
Corresponding author: Dr. M. Zhadobov Email: maxim.zhadobov@univ-rennes1.fr

Abstract

This paper deals with the numerical dosimetry for adult and children models exposed to CW signals of several wireless communication systems (UMTS, WiMax, and Bluetooth) within a partly shielded environment represented by a realistic car model. More than 20 mono- and multi-source exposure scenarios are considered. Computational results demonstrate that, for all considered exposure scenarios, the specific absorption rate (SAR) is at least 40 times (whole-body average) and 10 times (local SAR) lower than the exposure limits fixed by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). The whole-body average SAR values for children are found to be typically 1.1–1.3 times higher than those of adults. Under several exposure scenarios, the local SAR in the limbs of children models is 2–3 times higher than corresponding values in adult models. The power density distributions within the car have been also analyzed for one, two, and three simultaneously emitting devices. The results show that the homogeneity of the power density distribution increases with increasing number of simultaneously operating transmitters. These data suggest that the use of several wireless communication devices within a car leads to exposure levels that are several orders of magnitude below international exposure limits, even for the multi-exposure scenarios for both adult and children models.

Type
Research Papers
Copyright
Copyright © Cambridge University Press and the European Microwave Association 2011

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References

REFERENCES

[1]Anzaldi, G.; Silva, F.; Fernandez, M.; Quilez, M.; Riu, P.: Initial analysis of SAR from a cell phone inside a vehicle by numerical computation. IEEE Trans. Biomed. Eng., 54 (2007), 921930.CrossRefGoogle ScholarPubMed
[2]Ruddle, A.R.: Efficient estimation of human field exposure threats for vehicles with internal transmitters at microwave frequencies, in Proc. 16th ITS World Congress, Stockholm, Sweden, September 21–25, 2009.Google Scholar
[3]Zhang, H.; Low, L.; Rigelsford, J.; Langley, R.: Electromagnetic field mitigation within a cavity with vehicle-like features, in Proc. Fourth European Conf. Antenna Propagation, Barcelona, Spain, April 12–16, 2010.Google Scholar
[4]Low, L.; Zhang, H.; Rigelsford, J.; Langley, R.: Measured and computed in-vehicle field distributions, in Proc. Fourth European Conf. Antenna Propagation, Barcelona, Spain, April 12–16, 2010.Google Scholar
[5]Ruddle, A.; Low, L.; Zhang, H.; Rigelsford, J.; Langley, R.: Computed SAR and field exposure threat assessment for vehicle occupants, in Proc. Fourth European Conf. Antenna Propagation, Barcelona, Spain, Apr. 12–16, 2010.Google Scholar
[6]Chan, K.H.; Leung, S.W.; Siu, Y.M.: Specific absorption rate evaluation for people using wireless communication device in vehicle, in Proc. IEEE Int. Symp. Electromagnetic Compatibility (EMC), Fort Lauderdale, FL, USA, July 25–30, 2010, 706711.Google Scholar
[7]Simba, A.Y.; Hikage, T.; Watanabe, S.; Nojima, T.: Specific absorption rates of anatomically realistic human models exposed to RF electromagnetic fields from mobile phones used in elevators. IEEE Trans. Microwave Theory Tech., 57 (2009), 12501259.CrossRefGoogle Scholar
[8]Tropainen, A.: Human exposure by mobile phones in enclosed areas. Bioelectromagnetics, 24 (2003), 6365.CrossRefGoogle Scholar
[9]Ferrer, J.; Fernandez-Seivane, L.; Hernando, J.M.; Castan, M.B.; Garcia, L.; Vazquez, J.M.: On the exposure to mobile phone radiation in trains. Appl. Phys. Lett., 86 (2005), 224101.CrossRefGoogle Scholar
[10]Tang, C.K.; Chan, K.H.; Fung, L.C.; Leung, S.W.: Effect on radiofrequency human exposure of mobile phone inside an enclosed metallic elevator. Microwave Opt. Tech. Lett., 50 (2008), 22072210.CrossRefGoogle Scholar
[11]Ruddle, A.: Computed SAR levels in vehicle occupants due to on-board transmissions at 900 MHz, in Proc. Loughborough Antennas and Propagation Conf., Loughborough, UK, November 16–17, 2009, 137140.Google Scholar
[12]Ruddle, A.: Simulation of in-vehicle SAR levels at 900 MHz for a car with various transmitter positions and human occupancy configurations, in Proc. 31st Annual Meeting of the BEMS, Davos, Switzerland, June 15–19, 2009.Google Scholar
[13]Ruddle, A.: Influence of dielectric materials on in-vehicle electromagnetic fields, in Proc. IET Seminar on Electromagnetic Propagation in Structures and Buildings, London, UK, December 2008.Google Scholar
[14]Ruddle, A.R.; Ferrières, X.; Parmantier, J.P.; Ward, D.D.: Experimental validation of time-domain electromagnetic models for field coupling into the interior of a vehicle due to a nearby broadband antenna. IEE Proc. Sci. Meas. Technol., 151 (6) (2004), 430433.CrossRefGoogle Scholar
[15]Horiuchi, S.; Yamada, K.; Tanaka, S.; Yamada, Y.; Michishita, N.: Comparisons of simulated and measured electric field distributions in a cabin of a simplified scale car model. IEICE Trans. Commun., 90 (2007), 24082415.CrossRefGoogle Scholar
[16]Gandhi, O.P.; Lazzi, G.; Furse, C.: Electromagnetic absorption in the human head and neck for mobile telephones at 835 and 1900 MHz. IEEE Trans. Microw. Theory Tech., 44 (1996), 18841897.CrossRefGoogle Scholar
[17]De Salles, A.A.; Bulla, G.; Rodriguez, C.E.: Electromagnetic absorption in the head of adults and children due to mobile phone operation close to the head. Electromagn. Biol. Med., 25 (2006), 349360.CrossRefGoogle ScholarPubMed
[18]Schoenborn, F.; Burhardt, V.; Kuster, N.: Difference in energy absorption between heads of adults and children in the near field of sources. Health Phys., 74 (1998), 160168.CrossRefGoogle Scholar
[19]Wang, J.; Fujiwara, O.: Comparison and evaluation of electromagnetic absorption characteristics in realistic children for 900-MHz mobile telephones. IEEE Trans. Microw. Theory Tech., 51 (2003), 966971.CrossRefGoogle Scholar
[20]Peyman, A.; Gabriel, C.; Grant, E.H.; Vermeeren, G.; Martens, L.: Variation of the dielectric properties of tissues with age: the effect on the values of SAR in children when exposed to walkie-talkie devices. Phys. Med. Biol., 54 (2009), 227241.CrossRefGoogle ScholarPubMed
[21]Hadjem, A.; Lautru, D.; Dale, C.; Wong, M.F.; Hanna, V.F.; Wiart, J.: Study of specific absorption rate (SAR) induced in the two child head models and adult heads using mobile phones. IEEE Trans. Microw. Theory Tech., 53 (2005), 411.CrossRefGoogle Scholar
[22]Wiart, J. et al. : Modeling of RF head exposure in children. Bioelectromagnetics, S7 (2005), 1930.CrossRefGoogle Scholar
[23]Wiart, J.; Hadjem, A.; Wong, M.F.; Bloch, I.: Analysis of RF exposure in the head tissues of children and adults. Phys. Med. Biol., 53 (2008), 36813695.CrossRefGoogle ScholarPubMed
[24]Beard, B.B. et al. : Comparisons of computed mobile phone induced SAR in the SAM phantom to that in anatomically correct models of the human head. IEEE Trans. Electromagn. Compat., 48 (2006), 397407.CrossRefGoogle Scholar
[25]Keshvari, J.; Keshvari, R.; Lang, S.: The effect of increase in dielectric values on specific absorption rate (SAR) in eye and head tissues following 900, 1800 and 2450 MHz radio frequency (RF) exposure. Phys. Med. Biol., 51 (2006), 14631477.CrossRefGoogle ScholarPubMed
[26]Christ, A. et al. : Age dependent changes in SAR and temperature distribution induced in the user's head by cellular phones, in Proc. 30th Annual Meeting of BEMS, San Diego, CA, USA, June 8–12, 2008, 131.Google Scholar
[27]World Health Organization.: “Research agenda for radiofrequency fields,” 2010. [Online]. www.who.int/peh-emf/research/agenda.Google Scholar
[29]1528–2003, IEEE Recommended Practice for Determining the Peak Spatial-Average Specific Absorption Rate (SAR) in the Human Head From Wireless Communications Devices: Measurement Techniques, 2003.Google Scholar
[30]Schmid & Partner Engineering AG, SEMCAD X Tutorial, February 2010.Google Scholar
[32]ICNIRP.: Guidelines for limiting exposure to time-varying electric, magnetic, and electromagnetic fields (up to 300 GHz). Health Phys., 74 (1998), 494522.Google Scholar