volume | PIER Journals

Abstract

This paper proposes a new mobile handset antenna structure to reduce the value of the specific absorption rate (SAR). The antenna is based on the PIFA structure and operates at dual-bands of 0.9 GHz and 1.8 GHz. The chassis current is reduced using a metallic shim-layer inserted between the patch and chassis. This shim-layer is connected to the handset chassis through posts whose number and positions are determined using optimization techniques. Sidewalls are attached to increase the gain of the antenna and reduce the radiation towards human head. Simulations in the cheek mode show that the SAR reduction factor (SRF) of the proposed structure averaged over 10-g is more than 75% at 0.9 GHz and 46% at 1.8 GHz. The SRF values obtained using simulations and measurements are found to be better than 51% and 76% at 0.9 GHz and 1.8 GHz, respectively.

1. Christopoulou, M., S. Koulouridis and K. S. Nikita, "Parametric study of power absorption patterns induced in adult and child head models by small helical antennas," Progress In Electromagnetics Research, Vol. 94, 49-67, 2009.
doi:10.2528/PIER09031305 Google Scholar

2. Hirata, A., K. Shirai and O. Fujiwara, "On averaging mass of SAR correlating with temperature elevation due to a dipole antenna," Progress In Electromagnetics Research, Vol. 84, 221-237, 2008.
doi:10.2528/PIER08072704 Google Scholar

3. Mahmoud, K. R., M. El-Adawy, S. M. M. Ibrahem, R. Bansal and S. H. Zainud-Deen, "Investigating the interaction between a human head and a smart handset for 4G mobile communication systems," Progress In Electromagnetics Research C, Vol. 2, 169-188, 2008.
doi:10.2528/PIERC08032405 Google Scholar

4. Kouveliotis, N. K. and C. N. Capsalis, "Prediction of the SAR level induced in a dielectric sphere by a thin wire dipole antenna," Progress In Electromagnetics Research, Vol. 80, 321-336, 2008.
doi:10.2528/PIER07112804 Google Scholar

5. Ebrahimi-Ganjeh, M. A. and A. R. Attari, "Interaction of dual band helical and PIFA handset antennas with human head and hand ," Progress In Electromagnetics Research, Vol. 77, 225-242, 2007.
doi:10.2528/PIER07081804 Google Scholar

6. IEEE Std C95.1-2005 "Safety levels with respect to human exposure to radio frequency electromagnetic fields, 3 kHz to 300 GHz," IEEE Standard, 2006. Google Scholar

7. ICNIRP Guidelines "Guidelines for limiting exposure to time varying electric, magnetic and electromagnetic fields up to 300 GHz," Health Phys., Vol. 74, No. 4, 1998. Google Scholar

8. Lazzi, G., J. Johnson, S. S. Pattnaik and O. P. Gandhi, "Experimental study on compact, high-gain, low SAR single- and dual-band patch antenna for cellular telephones," IEEE Antennas and Propagation Society International Symposium, Vol. 1, 130-133, 1998. Google Scholar

9. Park, J. D., B. C. Kim and H. D. Choi, "A low SAR design of folder type handset with dual antennas," IEEE Antennas and Propagation Society International Symposium, Vol. 2, 1005-1008, 2003. Google Scholar

10. Cheng, P.-C., C.-Y.-D. Sim and C.-H. Lee, "Multi-band printed internal monopole antenna for mobile handset applications," Journal of Electromagnetic Waves and Applications, Vol. 23, No. 13, 1733-1744, 2009.
doi:10.1163/156939309789566978 Google Scholar

11. Zuo, S. L., Z. Y. Zhang and Y. Z. Yin, "A planar meander monopole antenna for DVB-H/GSM/DCS mobile handsets," Journal of Electromagnetic Waves and Applications, Vol. 23, No. 17-18, 2331-2337, 2009.
doi:10.1163/156939309790416107 Google Scholar

12. Kivekas, O., J. Ollikainen, T. Lehtiniemi and P. Vainikainen, "Bandwidth, SAR, and efficiency of internal mobile phone antennas," IEEE Trans. Electromagn. Compat., Vol. 46, No. 1, 71-86, 2004.
doi:10.1109/TEMC.2004.823613 Google Scholar

13. Saraereh, O. A., M. Jayawardene, P. McEvoy and J. C. Vardax-oglou, "Simulation and experimental SAR and efficiency study for a dual-band PIFA handset antenna (GSM 900/DCS 1800) at var-ied distance from a phantom head," IEE Antenna Measurements and SAR, 5-8, 2004.
doi:10.1049/ic:20040066 Google Scholar

14. Amos, S. V., M. S. Smith and D. Kitchmer, "Modeling of handset antenna interactions with the user and SAR reduction techniques," IEE National Conference on Antennas and Propagation, 12-15, York, UK, 1999. Google Scholar

15. Kitra, M. I., C. J. Panagamuwa, P. McEvoy, J. C. Vardaxoglou and J. R. James, "Low SAR ferrite handset antenna design," IEEE International Workshop on Antenna Technology Small Antennas and Novel Metamaterials, 144-147, 2006.
doi:10.1109/IWAT.2006.1608996 Google Scholar

16. Kitra, M. I., C. J. Panagamuwa, P. McEvoy, J. C. Vardaxoglou and J. R. James, "Low SAR ferrite handset antenna design," IEEE Trans. Antennas Propag., Vol. 55, No. 4, 1155-1164, 2007.
doi:10.1109/TAP.2007.893370 Google Scholar

17. Wang, J., O. Fujiwara and T. Takagi, "Effect of ferrite sheet attachment to portable telephone in reducing electromagnetic absorption in human head," IEEE International Symposium on Electromagnetic Compatibility, Vol. 2, 822-825, 1999. Google Scholar

18. Islam, M. T., M. R. I. Faruque and N. Misran, "Design analysis of ferrite sheet attachment for SAR reduction in human head," Progress In Electromagnetic Research, Vol. 98, 191-205, 2009.
doi:10.2528/PIER09082902 Google Scholar

19. Chou, H. H., H. T. Hsu, H. T. Chou, K. H. Liu and F. Y. Kuo, "Reduction of peak SAR in human head for handset applications with resistive sheets (R-Cards)," Progress In Electromagnetic Research, Vol. 94, 281-296, 2009.
doi:10.2528/PIER09062702 Google Scholar

20. Chan, K. H., L. C. Fung, S. W. Leung and Y. M. Siu, "Effect of internal patch antenna ground plane on SAR," 17th International Zurich Symposium on Electromagnetic Compatibility, 513-516, 2006.
doi:10.1109/EMCZUR.2006.214984 Google Scholar

21. SEMCAD. SEMCAD Manual, Available online at http://www.semcad.com..

22. DASY5 Documentation, manufactured by SPEAG, http://www.speag.com..

23. Kusuma, A. H., "Antenna design for mobile terminals based on interactions with the human body ," MS Thesis, King Saud University, Riyadh, Saudi Arabia, 2010. Google Scholar

24. Elshafiey, I., A.-F. Sheta, S. Aldosari, M. A. Alkanhal and S. A. Alshebeili, "Multiobjective optimization for low SAR antenna design," IEEE International Symposium on Signal Processing and Information Technology (ISSPIT), 213-218, 2009.
doi:10.1109/ISSPIT.2009.5407578 Google Scholar

25. IEEE Std 1528-2003 "IEEE Recommended practice for determin-ing the peak spatial-average specific absorption rate (SAR) in the human head from wireless communications devices: Measurement techniques," IEEE Standard, 2003. Google Scholar

26. Du, Z., K. Gong and J. S. Fu, "A novel compact wide-band planar antenna for mobile handsets," IEEE Trans. Antennas Propag., Vol. 54, No. 2, 613-619, 2006.
doi:10.1109/TAP.2005.863088 Google Scholar

27. Ali, M., G. J. Hayes, H.-S. Hwang and R. A. Sadler, "Design of a multiband internal antenna for third generation mobile phone handsets,", Vol. 51, No. 7, 1452-1461, 2003.
doi:10.1109/TAP.2003.812282 Google Scholar

Mr. Andi Hakim Kusuma

Dr. Abdel-Fattah Sheta

Prof. Ibrahim Elshafiey

Dr. Zeeshan Siddiqui

Professor Majeed Alkanhal

Dr. Saeed Aldosari

Dr. Saleh A. Alshebeili

Professor Samir Mahmoud