volume | PIER Journals

Abstract

The goal of this study is to analyze the effect of tri-band antennas in 2.45, 3.6, 3.8, 4.56 and 6 GHz frequencies, which cover Wi-Fi and some of the future 5G frequencies for wearable smart glasses applications. The latter 4 frequencies are studied for the first time for smart glasses. In order to provide a thorough analysis, first a simulation study for the head model with the proposed antennas is performed, then a realistic experiment by using a semi-liquid gel phantom head model with the infrared thermography method is conducted, and also 4 male subjects are included to analyze temperature rise effects on the skin. The phantom prepared for this study is also validated for its robustness and matching parameters. The SAR values and temperature rise due to the usage of smart glasses calculated by simulation modeling, bio-heat analytical solution, and infrared thermography technique are in good agreement. The temperature rise of the skin regions gets monotonically increased in the duration of usage. The simulations for all indicated frequencies are performed. Also, to provide comparable and practical results, the phantom study is compared with simulations for 2.45 GHz. According to the quantitative data obtained on the liquid-gel head phantom and on the subjects, the temperature increase is below 1ºC, and its compliance with safety standards is determined. The results show that tri-band antennas for these frequencies can be safely used; however, a limiting behavior for the power is necessary for lower frequencies due to the increasing SAR values and temperature rise.

1. Varshini, K. and T. Rama Rao, "Estimation of specific absorption rate using infrared thermography for the biocompatibility of wearable wireless devices," Progress In Electromagnetics Research, Vol. 56, 101-109, 2017.

2. Lahiri, B., S. Bagavathiappan, C. Soumya, T. Jayakumar, and J. Philip, "Infrared thermography based studies on mobile phone induced heating," Infrared Physics & Technology, Vol. 71, 242-251, 2015.

3. Repacholi, M. H., "Low-level exposure to radiofrequency electromagnetic fields: Health effects and research needs," Bioelectromagnetics: Journal of the Bioelectromagnetics Society, the Society for Physical Regulation in Biology and Medicine, the European Bioelectromagnetics Association, Vol. 19, No. 1, 1-19, 1998.

4. Zhang, M. and X. Wang, "Influence on SAR due to metallic frame of glasses based on high-resolution Chinese electromagnetic human model," 2010 Asia-Pacific Symposium on Electromagnetic Compatibility (APEMC), 48-51, IEEE, 2010.

5. Pizarro, Y., A. De Salles, S. Severo, J. Garzon, and S. Bueno, "Specific Absorption Rate (SAR) in the head of Google glasses and Bluetooth user’s," 2014 IEEE Latin-America Conference on Communications (LATINCOM), 1-6, IEEE, 2014.

6. Bellanca, G., G. Caniato, A. Giovannelli, P. Olivo, S. J. M. Trillo, and O. T. Letters, "Effect of field enhancement due to the coupling between a cellular phone and metallic eyeglasses," Microwave & Optical Technology Letters, Vol. 48, No. 1, 63-65, 2006.

7. Cihangir, A., et al., "Dual-band 4G eyewear antenna and SAR implications," IEEE Transactions on Antennas and Propagation, Vol. 65, No. 4, 2085-2089, 2017.

8. Cihangir, A., C. J. Panagamuwa, W. G. Whittow, F. Gianesello, C. J. I. A. Luxey, and W. P. Letters, "Ultra-broadband antenna with robustness to body detuning for 4G eyewear devices," IEEE Antennas and Wireless Propagation Letters, Vol. 16, 1225-1228, 2017.

9. Cihangir, A., W. Whittow, C. Panagamuwa, G. Jacquemod, F. Gianesello, and C. J. C. R. P. Luxey, "4G antennas for wireless eyewear devices and related SAR," Comptes Rendus Physique, Vol. 16, No. 9, 836-850, 2015.

10. Cihangir, A., et al., "Feasibility study of 4G cellular antennas for eyewear communicating devices," IEEE Antennas and Wireless Propagation Letters, Vol. 12, 1704-1707, 2013.

11. Lan, J., X. Liang, T. Hong, G. J. P. I. b. Du, and M. Biology, "On the effects of glasses on the SAR in human head resulting from wireless eyewear devices at phone call state," Progress in Biophysics and Molecular Biology, Vol. 136, 29-36, August 2018.

12. Tikhomirov, A., E. Omelyanchuk, and A. Semenova, "Recommended 5G frequency bands evaluation," 2018 Systems of Signals Generating and Processing in the Field of on Board Communications, 2018.

13. Letavin, D. A. and D. A. Trifonov, "Simulation of 3600–3800 MHz frequency band antenna for fifth generation mobile communication," 2018 Ural Symposium on Biomedical Engineering, Radioelectronics and Information Technology (USBEREIT), 291-294, IEEE, 2018.

14. Qamar, F., M. H. S. Siddiqui, K. Dimyati, K. A. B. Noordin, and M. B. Majed, "Channel characterization of 28 and 38GHz MM-wave frequency band spectrum for the future 5G network," 2017 IEEE 15th Student Conference on Research and Development (SCOReD), 291-296, IEEE, 2017.

15. Pandit, S., A. Mohan, and P. J. I. S. L. Ray, "Compact frequency-reconfigurable MIMO antenna for microwave sensing applications in WLAN and WiMAX frequency bands," IEEE Sensors Letters, Vol. 2, No. 2, 1-4, 2018.

16. Karthik, V. and T. R. Rao, "Investigations on SAR and thermal effects of a body wearable microstrip antenna," Wireless Personal Communications, Vol. 96, No. 3, 3385-3401, 2017.

17. Varshini, K. and T. Rama Rao, "Thermal distribution based investigations on electromagnetic interactions with the human body for wearable wireless devices," Progress In Electromagnetics Research M, Vol. 50, 141-150, 2016.

18. Brishoual, M., C. Dale, J. Wiart, and J. Citerne, "Methodology to interpolate and extrapolate SAR measurements in a volume in dosimetric experiment," IEEE Transactions on Electromagnetic Compatibility, Vol. 43, No. 3, 382-389, 2001.

19. Chavannes, N., R. Tay, N. Nikoloski, and N. Kuster, "RF design of mobile phones by TCAD: Suitability and limitations of FDTD," IEEE Antennas Propagation Mag., Vol. 45, 52-66, 2003.

20. Mobashsher, A. T. and A. M. Abbosh, "Artificial human phantoms: Human proxy in testing microwave apparatuses that have electromagnetic interaction with the human body," IEEE Microwave Magazine, Vol. 16, No. 6, 42-62, 2015.

21. Bakar, A. A., A. Abbosh, P. Sharpe, and M. Bialkowski, "Artificial breast phantom for microwave imaging modality," 2010 IEEE EMBS Conference on Biomedical Engineering and Sciences (IECBES), 385-388, IEEE, 2010.

22. Islam, M. T., M. Samsuzzaman, S. Kibria, and M. T. Islam, "Experimental breast phantoms for estimation of breast tumor using microwave imaging systems," IEEE Access, Vol. 6, 78587-78597, 2018.

23. Duan, Q., et al., "Characterization of a dielectric phantom for high-field magnetic resonance imaging applications," Medical Physics, Vol. 41, No. 10, 102303, 2014.

24. Soler Gonzalez, F., "Radiation effects of wearable antenna in human body tissues," EEE Student Reports (FYP/IA/PA/PI), 2014.

25. Castello-Palacios, S., C. Garcia-Pardo, A. Fornes-Leal, N. Cardona, and A. Valles-Lluch, "Wideband phantoms of different body tissues for heterogeneous models in body area networks," 2017 39th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), 3032-3035, IEEE, 2017.

26. Castello-Palacios, S., C. Garcia-Pardo, A. Fornes-Leal, N. Cardona, and A. Valles-Lluch, "Tailor-made tissue phantoms based on acetonitrile solutions for microwave applications up to 18 GHz," IEEE Transactions on Microwave Theory and Techniques, Vol. 64, No. 11, 3987-3994, 2016.

27. Destruel, A., et al., "A numerical and experimental study of RF shimming in the presence of hip prostheses using adaptive SAR at 3 T," Magnetic Resonance in Medicine, 2019.

28. Simba, A., S. Watanabe, T. Hikage, and T. Nojima, "Experimental and numerical investigation of the maximum specific absorption rate in a spherical phantom when operating a mobile phone near a metallic wall," IET Science, Measurement & Technology, Vol. 5, No. 6, 225-230, 2011.

29. Abdelsamie, M. A., S. Mustafa, M. Isa, and D. Hashim, "Evaluation of electric and magnetic fields distribution and SAR induced in 3D models of water containers by radiofrequency radiation and their relationship to the non-thermal effects of microwaves,", arXiv preprint arXiv:1410.2147, 2014.

30. Wessapan, T., S. Srisawatdhisukul, and P. Rattanadecho, "Specific absorption rate and temperature distributions in human head subjected to mobile phone radiation at different frequencies," International Journal of Heat and Mass Transfer, Vol. 55, No. 1–3, 347-359, 2012.

31. Hamada, L., T. Iyama, T. Onishi, and S. Watanabe, "The specific absorption rate of mobile phones measured in a flat phantom and in the standardized human head phantom," EMC09 21S4-1, 245-247, 2009.

32. Alon, L., D. K. Sodickson, and C. M. Deniz, "Heat equation inversion framework for average SAR calculation from magnetic resonance thermal imaging," Bioelectromagnetics, Vol. 37, No. 7, 493-503, 2016.

33. Foster, K. R., "Thermal and nonthermal mechanisms of interaction of radio-frequency energy with biological systems," IEEE Transactions on Plasma Science, Vol. 28, No. 1, 15-23, 2000.

34. Sarimov, R., L. O. Malmgren, E. Markova, B. R. Persson, and I. Y. Belyaev, "Nonthermal GSM microwaves affect chromatin conformation in human lymphocytes similar to heat shock," IEEE Transactions on Plasma Science, Vol. 32, No. 4, 1600-1608, 2004.

35. Huber, E., M. Mirzaee, J. Bjorgaard, M. Hoyack, S. Noghanian, and I. Chang, "Dielectric property measurement of PLA," 2016 IEEE International Conference on Electro Information Technology (EIT), 0788-0792, IEEE, 2016.

36. https://www.omicsonline.org/universities/Italian National Research Council/.

37. La Gioia, A., et al., "Open-ended coaxial probe technique for dielectric measurement of biological tissues: Challenges and common practices," Diagnostics, Vol. 8, No. 2, 40, 2018.

38. Zajıcek, R. and J. Vrba, "Broadband complex permittivity determination for biomedical applications," Advanced Microwave Circuits and Systems, 365-385, IntechOpen, 2010.

39. https://speag.swiss/products/em-phantoms/phantoms/sam-v4-5bs/.

40. I. S. C. C. 34 "IEEE recommended practice for determining the peak spatial-average Specific Absorption Rate (SAR) in the human head from wireless communications devices: Measurement techniques," Standard 1528-2003, Institute of Electrical and Electronic Engineers, 2003.

41. Kritikos, H. and H. P. Schwan, "Potential temperature rise induced by electromagnetic field in brain tissues," IEEE Transactions on Biomedical Engineering, Vol. 26, No. 1, 29-34, 1979.

Dr. Miraç Dilruba Geyikoğlu

Dr. Fatih Kaburcuk

Dr. Bülent Çavusoğlu