PHANTOM MODEL OF HUMAN BRAIN TISSUE FOR CELLULAR PHONE FREQUENCIES IN ELECTROMAGNETIC FIELD RADIATION ABSORPTION STUDIES

Abstract

ABSTRACT

There is a necessity of tissue equivalent (phantom) models in research of electromagnetic (EM) effects in biologic tissues. Recently, many kinds of tissue models depend on the different aim were proposed. So many studies were carried on the interaction of human-head and cellular phone. The most of them are related to numerical models. Owing to difficulty of study on human body, simulation of human tissues is required. In this study two different, for 900MHz and for 1800MHz, brain equivalent tissues have been prepared and their electrical features were evaluated by taking into consideration of mixing rates.

Keywords

• Key Words: Brain equivalent tissue, RF absorption, GSM, Phantom model

HÜCRESEL TELEFON FREKANSLI ELEKTROMANYETİK RADYASYON SOĞURULMASI ARAŞTIRMALARI İÇİN İNSAN BEYİN DOKUSU FANTOM MODELİ

Abstract

Biyolojik dokularda elektromanyetik (EM) etkilerin araştırılması için doku eşdeğer modellerine gereksinim duyulmaktadır. Son zamanlarda bu amaçla değişik araştırmalara yönelik doku modelleri önerilmektedir. Cep telefonları ve insan kafası etkileşimi üzerine çok fazla araştırma yapılmaktadır. Bu araştırmaların çoğunluğu sayısal model çalışmalarından oluşmaktadır. İnsan üzerinde deneysel çalışmaların zor olması nedeniyle biyolojik dokuların simüle edilmesi gerekmektedir. Bu çalışmada 900MHz ve 1800MHz için iki ayrı beyin eşdeğer dokusu hazırlanmış ve karışım oranları dikkate alınarak elektriksel özellikleri belirlenmiştir

Keywords

• Beyin eşdeğer dokusu, RF soğurulma, GSM, Fantom model

References

1. Bernardi, P., Canagnaro, M., Pisa, S., and Puizzi, E., “SAR distribution and temperature increase in an anatomical model of the human eye exposed to the field radiated by the user antenna in a wireless LAN”, IEEE Trans. Microwave Theory and Techniques, Vol.46:2074-2082, (1998).
2. Fujiwara, O., And Takai, K., “Electrical properties of skin and SAR calculation in a realistic human model microwave exposure”, Electrical Engineering in Japan, Vol.120: 66-73, (1997)
3. Furse, C.M., Chen, C.Y., And Ghandhi, O.P., “The use of the frequency-dependent finite-difference time domain method for induced current and SAR calculations for a heterogeneous model of human body”, IEEE Trans. Vol.EMC-36: 128-133, No.2, (1994).
4. Schwan, HP., and Piersol, G.M., “The absorption of electromagnetic energy in body tissues”, Amer. J. Phys. Med. Vol. 33: 371-404, (1954).
5. Stuchly, MA., and Stuchly, S.S., “Electrical properties of biological substances”. in Gandhi Op. (ed): Biological effects and medical applications of electromagnetic energy. Englewood Cliffs, NJ: Prentice Hall, pp. 75-112, (1990).
6. Durney, CH., Massoudi, H., and Iskender, MF., Radiofrequency dosimetry handbook, 4th Ed., Brooks Air Fors Base, Taxas., (1986).
7. Gabriel, C., “Compilation of the dielectric properties of body tissues at RF and microwave frequencies” Brooks air force technical report AL/OE-TR-1996-0037. Armstrong Laboratory, Brooks Air Force Base, TX.,(1996).
8. Foster, Kr., and Schwan, HP., “Dielectric permittivity and electrical conductivity of biological materials. In Polk C, Postow E (eds): Handbook of biological effects of electromagnetic fields. Boca Raton, FL: CRC Press, 27-96 (1986).

9. Jerry, L., Ulcek Robert, F., Clevand, JR., “Federal communication commission office of engineering & technology, information on human exposure to radiofrequency fields from cellular and PCS radio transmitters”, Bulletin 65, Editions 97-01, Washington, (1997).
10. Hartsgrove, G., Kraszewski, A., and Surowiec, “Simulated biological materials for electromagnetic radiation absorption studies”, Bioelectromagnetics, vol.8: 26-36 (1997).
11. Gandhi, O.P., Lazzi, G., Tinniswood, A., and Yu, Q.S., “Comparison of numerical and experimental methods for determination of SAR and radiation patterns of handheld wireless telephones”, Bioelectromagetics, vol.20: 93-101 (1999).
12. Chou, Ck., Chen, GW., Guy, AW., and Luk, KH., “Formulas for preparing phantom muscle tissue at various radiofrequencies”, Bioelectromagnetics, vol. 5, pp. 435-441 (1984).
13. Stuchly, MA., and Stuchly, SS., Electrical properties of biological substances. in Gandhi Op. (ed): "Biological effects and medical applications of electromagnetic energy. Englewood Cliffs, NJ: Prentice Hall, 75-112 (1990).
14. Michael B., Kuster, N., “Appropriate modeling of the ear for compliance testing of handheld with SAR safety limits at 900/1800MHz”, IEEE Trans. Microwave Theory Tech., vol.48:1927-34, no.11, (2000).
15. Iskander, M.F., Yun, Z., and Quintero-Illera, R., “A fine grid computation domain was used for modeling the head”, IEEE Trans. Microwave Theory Tech., vol.48, no.11: 1979-1987, (2000).
16. Masaaki, Yano., Jianqing, Wang, and Fujiwara, O., “FDTD computation of temperature rise in realistic head models simulating adult and infant for 1.5GHz microwave exposure”, Electronics and Communications in Japon, Part.1, Vol. 84, No. 4, (2000).
17. Yoshinobu, O., Koichi, I., Ichiro, I., and, Masaharu, T., “The SAR evaluation method by a combination of thermographic experiments and biological tissue-equivalent phantoms”, IEEE Trans. Microwave Theory Tech, vol.48, no.11: 2094-2103, (2000).
18. Kuster, and Balzano Q, “Energy absorption mechanism by biological bodies in the near field of dipole antennas above 300 MHz”, IEEE Transactions on Vehicular Technology, Vol.41: 17-23, (1992).
19. Quishan Yu, et. All., “An automated SAR measurement system for compliance testing of personal wireless devices”, IEEE Transaction on Electromagnetic Compatibility, Vol.41, No.3: 234-245,August (1999).