This paper analyzes and discusses the effect of the electromagnetic absorption by human head against variation of head dielectric properties at 900, 1800 and 1900 MHz. The characteristics of helical antenna and its substrates with variation in human head dielectric properties are simulated by implementing finite-difference time-domain (FDTD) method using CST Microwave studio. The variations in human head dielectric properties were manipulated by increasing and decreasing 10% and 20% of each of the human head dielectric properties. In this paper, SAR values increase with increment of head conductivity, and increment of head permittivity and head density lead to decrement of SAR values. Helical antenna with substrate of FR4 results in higher SAR values in all frequency exposures. The head SAR values are higher with higher frequency exposures. The helical antenna with substrate of Rogers RO3006 (loss free) is found to be better over FR4 and Rogers RO4003 (loss free), which contributes towards much lower SAR values in all GSM frequency bands exposure.
2. Keshvari, , J., , R. Keshvari, and S. Lang, , "The effect of increase in dielectric values on specific absorption rate (SAR) in eye and head tissues following 900, 1800 and 2450MHz radio frequency (RF) exposure," Phys. Med. Biol., Vol. 51, 1463-1477, 2006.
3. Zhang, M. and A. Alden, "Calculation of whole-body SAR from a 100MHz dipole antenna," Progress In Electromagnetics Research, Vol. 119, 133-153, 2011..
4. Islam, M. T., M. R. I. Faruque, and N. Misran, "Design analysis of ferrite sheet attachment for SAR reduction in human head," Progress In Electromagnetics Research, Vol. 98, 191-205, 2009.
5. Otin, , R. and H. Gromat, "Specific absorption rate computations with a nodal-based finite element formulation," Progress In Electromagnetics Research, Vol. 128, 399-418, 2012.
6. Islam, , M. T., H. Z. Abidin, M. R. I. Faruque, and N. Misran, "Analysis of materials effects on radio frequency electromagnetic fields in human head," Progress In Electromagnetics Research, Vol. 128, 121-136, 2012.
7. Faruque, M. R. I., , M. T. Islam, and N. Misran, "Design analysis of new metamaterial for EM absorption reduction," Progress In Electromagnetics Research, Vol. 124, 119-135, 2012.
8. Wang, , J., , Z. Zhao, J. Song, X. Zhu, Z.-P. Nie, and Q. H. Liu, "Reconstruction of microwave absorption properties in heterogeneous tissue for microwave-induced thermo-acoustic tomography ," Progress In Electromagnetics Research, Vol. 130, 225-240, 2012.
9. Vidal, N., S. Curto, J. M. Lopez-Villegas, J. Sieiro, and F. M. Ramos, "Detuning study of implantable antennas inside the human body, ," Progress In Electromagnetics Research, Vol. 124, 265-283, 2012.
10. Carlberg, , M., L. Hardell, V. G. Khurana, M. Kundi, and C. Teo, "Cell phones and brain tumors: A review including the long-term epidemiologic data ," Surgical Neurology, Vol. 72, No. 3, 214-215, 2009.
11. Hardell, L. , M. Carlberg, and , "Mobile phone, cordless phone and risk of brain tumors ," International Journal of Oncology,, Vol. 35, No. 1, 5-17, 2009.
12. CNN, WHO, "Cell phone use increase possible cancer risk,", 2011.
13. Vrbova, , B. and J. Vrba, "Microwave thermotherapy in cancer treatment: Evaluation of homogeneity of SAR distribution," Progress In Electromagnetics Research, Vol. 129, 181-195, 2012.
14. Golestanirad, , L., A. P. Izquierdo, S. J. Graham, J. R. Mosig, and C. Pollo, "Effect of realistic modeling of deep brain stimulation on the prediction of volume of activated tissue," Progress In Electromagnetics Research,, Vol. 126, 1-16, 2012.
15. Ibrani, M., L. Ahma, E. Hamiti, and J. Haxhibeqiri, "Derivation of electromagnetic properties of child biological tissues at radio frequencies," Progress In Electromagnetics Research Letters,, Vol. 25, 87-100, 2011.
16. Otin, , R., , "Numerical study of the thermal effects induced by a RFID antenna in vials of blood plasma," Progress In Electromagnetics Research Letters, Vol. 22, 129-138, 2011.
17. Caratelli, , D., A. G. Yarovoy, A. Massaro, and A. Lay-Ekuakille, "Design and full-wave analysis of piezoelectric micro-needle antenna sensors for enhanced nearfield detection of skin cancer ," Progress In Electromagnetics Research, Vol. 125, 391-413, 2012.
18. Behari, , J., "Biological responses of mobile phone frequency exposure," Indian J. Exp. Biol.,, Vol. 48, No. 10, 959-981, 2010.
19. Zhao, L. , K.-L. Wu, and , "A hybrid NFM/MoM full-wave analysis of layered prolate head model exposed to handset antenna," Progress In Electromagnetics Research, Vol. 123, 205-225, 2012.
20. Gandhi, , O. P. and G. Kang, "Some present problems and proposed experimental phantom for SAR compliance testing of cellular telephones at 835 and 1900 MHz," Phys. Med. Biol., Vol. 47, No. 9, 1501-1518, 2002.
21. International Commission on Non-ionizing Radiation Protection, "Health issues related to the use of hand-held radiotelephones and base transmitter ," Health Phys., Vol. 70, 587-593, 1996.
22. Yanase, K. and A. Hirata, "Effective resistance of grounded humans for whole body averaged SAR estimation at resonance frequencies," Progress In Electromagnetics Research B,35, Vol. 35, 15-27, 2011.
23. Federal Communications Commission, "Evaluating compliance with FCC guidelines for human exposure to radiofrequency electromagnetic field,", 2001.
24. Kusuma, , A. H., A.-F. Sheta, I. M. Elshafiey, Z. Siddiqui, M. A. S. Alkanhal, S. Aldosari, S. A. Alshebeili, and S. F. Mahmoud, "A new low SAR antenna structure for wireless handset applications," Progress In Electromagnetics Research, Vol. 112, 23-40, 2011.
25. Lkeuchi, R., K. H. Chan, and A. Hirata, "SAR and radiation characteristics of a dipole antenna above different finite EBG substrates in the presence of a realistic head model in the 3.5 GHz band," Progress In Electromagnetics Research B, Vol. 44, 53-70, 2012.
26. Montaser, , A. M., K. R. Mahmoud, and H. A. Elmikati, "An interaction study between PIFAs handset antenna and a human hand-head in personal communications ," Progress In Electromagnetics Research B, Vol. 37, 21-42, 2012.
27. Ronald, , S. H., M. F. B. A. Malek, S. H. Idris, E. M. Cheng, M. H. Mat, M. S. Zulke°i, and S. F. Binti Maharimi, "Designing asian-sized hand model for SAR determination at GSM900/1800: Simulation part," Progress In Electromagnetics Research, Vol. 129, 439-467, 2012.
28. Gaj·sek, , P., W. D. Hurt, P. A. Mason, and J. M. Ziriax, "Parametric dependence of SAR on permittivity values in a man model ," IEEE Transactions on Biomedical Engineering, Vol. 48, No. 10, 1169-1177, 2001.
29. Bao, , J. Z., W. D. Hurt, and S. T. Lu, "Complex dielectric measurements and analysis of brain tissues in the radio and microwave frequencies," IEEE Trans. Microw. Theory Tech., Vol. 45, No. 10, 1730-1741, 1997.
30. Faruque, M. R. I., M. T. Islam, and N. Misran, "Analysis of electromagnetic absorption in the mobile Phones Using Metamaterials," Electromagnetics Journal, Vol. 31, No. 3, 215-232, 2011.
31. Kong, , L.-Y., J. Wang, and W.-Y. Yin, "A novel dielectric conformal FDTD method for computing SAR distribution of the human body in a metallic cabin illuminated by an intentional human body in a metallic cabin illuminated by an intentional electromagnetic pulse (IEMP)," Progress In Electromagnetics Research, Vol. 126, 355-373, 2012.
32. Chen, , Z., Y.-L. Ban, J.-H. Chen, J. L.-W. Li, and Y.-J. Wu, "Bandwidth enhancement of LTE/WWAN printed mobile phone antenna using slotted ground structure, ," Progress In Electromagnetics Research,, Vol. 129, 469-483, 2012.
33. Fujiwara, , O., J. Q. Wang, and S. Watanabe, "Approximation of aging on dielectric tissue properties for SAR assessment of mobile telephones," IEEE Trans. Electromagn. Compat., Vol. 48, No. 2, 408-413, 2006.
34. Khalatbari, , S., D. Sardari, A. A. Mirzaee, and H. A. Sadafi, "Calculating SAR in two models of the human head exposed to mobile phones radiations at 900 and 1800 MHz," PIERS Proceedings, 104-109, 2006..
35. Rojas, , R., , S. E. Solis, and A. O. Rodriguez, "Numerical Simulation of Speci¯c absorption rate and induced currents in a rat's Pixel Brain due to Radiofrequency Fields," PIERS Proceedings,, 1020-1023, 2009.
36. Gabriel, S., , R. W. Lau, and C. Gabriel, "The dielectric properties of biological tissues: III. Parametric models for the dielectric spectrum of tissues," Physics in Medicine and Biology, Vol. 41, No. 11, 2271-2293, 1996.
37. Lee, K. H., I. Ahmed, R. S. M. Goh, E. H. Khoo, E. P. Li, and T. G. G. Hung, "Implementation of the FDTD method based on Lorentz-Drude dispersive model on GPU for plasmonics applications," Progress In Electromagnetics Research, Vol. 116, 441-456, 2011.
38. Izadi, , M., M. Z. A. Ab Kadir, and C. Gomes, "Evaluation of electromagnetic fields associated with inclined lightning channel using second order FDTD-hybrid methods," Progress In Electromagnetics Research, Vol. 117, 209-236, 2011.