This paper presents the design of a flexible antenna using planar dipole with a reflector to achieve optimal radiation efficiency and low specific absorption rate (SAR) when the antenna is placed directly over the skin of body model. The antenna is designed for the 2.45 GHz frequency band. The parametric analysis of the proposed antenna is carried out. The proposed antenna achieves stable on-body performance: |S11| varies from -16.05 dB (on skin) at 2.47 GHz resonant frequency to -16.40 dB (on skin) at 2.47 GHz resonant frequency to -16.40 dB (in free space) at 2.44 GHz resonant frequency. It was found that the maximum 1 g average SAR value is only 0.23 W/kg for an input power of 100 mW when the antenna is placed directly over the skin of a three-layer body model, and radiation efficiency is 20.5%. The measured results are presented to demonstrate the validity of the proposed antenna.
"A Flexible Planar Antenna on Multilayer Rubber Composite for Wearable Devices," Progress In Electromagnetics Research C,
Vol. 75, 31-42, 2017. doi:10.2528/PIERC17031701
1. Chen, J. W. and H. Mitomo, "The underlying factors of the perceived usefulness of using smart wearable devices for disaster applications," Telematics and Informatics, Vol. 34, 528-539, 2017. doi:10.1016/j.tele.2016.09.010
2. Yang, H., W. Yao, Y. Yi, X. Huang, S. Wu, and B. Xiao, "A dual-band low-profile metasurfaceeanabled wearable antenna for WLAN devices," Progress In Electromagnetic Research, Vol. 61, 115-125, 2016. doi:10.2528/PIERC15092803
3. Genovesi, S., F. Costa, F. Fanciulli, and A. Monorchio, "Wearable inkjet-printed wideband antenna by using miniaturized AMC for sub-GHz applications," IEEE Antennas and Wirelesss Propagation Letter, Vol. 15, 4027-4030, 2016.
4. Al-Ghamdi, A., O. Al-Hartomy, F. Al-Solamy, N. Dishovsky, N. Atanasov, and G. Atanasova, "Enhancing antenna performance and SAR reduction by a conductive composite loaded with carbon-silica hybrid filler," International Journal of Electronics and Communications (AEU), Vol. 70, 668-675, 2017.
5. Jiang, Z., D. Brocker, P. Sieber, and D. Werner, "A compact, low-profile metasurface-enabled antenna for wearable medical body-area network devices," IEEE Trans. Antennas Propag., Vol. 62, 4021-4030, 2014. doi:10.1109/TAP.2014.2327650
6. Velan, S., E. Florence, M. Kanagasabai, A. Sarma, C. Reviteja, R. Sivasamy, and J. Pakkathillam, "Dual-band EBG integrated monopole antenna deploying fractal geometry for wearable applications," Antennas Wireless Propag. Lett., Vol. 14, 249-252, 2015. doi:10.1109/LAWP.2014.2360710
7. Raad, H., A. Abbosh, H. Al-Rizzo, and D. Rucker, "Flexible and compact AMC based antenna for telemedicine applications," Antennas Wireless Propag. Lett., Vol. 61, 524-531, 2013. doi:10.1109/TAP.2012.2223449
8. Chen, Y. and T. Ku, "A low-profile wearable antenna using a miniature high impedance surface for smart watch applications," Antennas Wireless Propag. Lett., Vol. 15, 1144-1147, 2016. doi:10.1109/LAWP.2015.2496366
9. Abbas, S. M., K. Esselle, and Y. Ranga, "A printed antenna with a ground plane and electromagnetically coupled feed for 2.45GHz body area networks," APSURSI, IEEE, 2143-2144, 2013.
10. Affendi, N. A. M., N. A. L. Alias, N. M. Razali, Z. Awang, and A. Samsuri, "Flexible antennas using a new material," Proceedings of Asia-Pacific Microwave Conference, 1420-1422, 2014.
11. Zaiki, A., N. A. M. Affendi, N. A. L. Alias, and N. M. Razali, "Flexible antennas based on natural rubber," Progress In Electromagnetic Research, Vol. 61, 75-90, 2016. doi:10.2528/PIERC15092501
12. Chen, L. F., C. K. Ong, C. Neo, V. V. Varadan, and V. K. Varadan, Microwave Electronics: Measurement and Materials Characterization, 1st Ed., John Wiley & Sons, Ltd., Chichester, 2004. doi:10.1002/0470020466
13. Raad, H. K., H. M. Al-Rizzo, A. Issac, and A. I. Hammoodi, "A compact dual band polyimide based antenna for wearable and flexible telemedicine devices," Progress In Electromagnetics Research C, Vol. 63, 153-161, 2016. doi:10.2528/PIERC16010707
14. Hu, B., G.-Gao, L.-L. He, X.-D. Cong, and J.-N. Zhao, "Bending and on-arm effects on a wearable antenna for 2.45GHz body area network," IEEE Antennas Wireless Propag. Lett., Vol. 15, 378-381, 2015. doi:10.1109/LAWP.2015.2446512
16. Fujimoto, K., "Antennas for mobile communications," Modern Antenna Handbook, 1143-1228, C. A. Balanis editor, Hoboken, John Wiley & Sons, Inc., 2008.
17. Yialmaz, T., R. Foster, and Y. Hao, "Broadband tissue mimicking phantoms and a patch resonator for evaluation noninvasive monitoring of blood glucose levels," IEEE Trans. Antennas Propag., Vol. 62, 3065-3075, 2014.
18., , IEEE for Recommended Practice for Determining the Peak Spatial-Average Specific Absorption Rate (SAR) in the Human Head from Wireless Communications Devices: Measurement Techniques, IEEE Standard 1528, 2003.
19. Varnoosfaderani, M. V., D. V. Thiel, and J. Lu, "External parasitic elements on clothing for improved performance of wearable antennas," IEEE Sensors Journal, Vol. 15, No. 1, 307-315, 2015. doi:10.1109/JSEN.2014.2343245