volume | PIER Journals

Abstract

This paper presents a miniaturized antenna-based wearable self-powered wireless systems; the proposed study identifies the possibility to compact a flexible Solant-Rectenna integrated to low energy devices. The proposed system uses the obtained DC currents from RF rectifier and solar panel to recharge batteries. A low-profile Hilbert-shaped metamaterial (MTM) array forming a rectangular patch is conducted to minimize the shadowing effects to 13.3% on the solar panel area. Nevertheless, an Electromagnetic Bandgap (EBG) square pads array is introduced as defects on the ground plane to remove the negative effects, in terms of losses, of the solar panel bus-bar on the antenna performance. Moreover, the proposed EBG ground plane is utilized to isolate the human body from the undesired electromagnetic radiation leakage in addition to minimize the antenna impedance mismatch caused by the proximity to human tissues. For this, the Specific Absorption Rate (SAR) is analysed numerically to assess the feasibility of the proposed EBG layer. The antenna expresses a frequency bandwidth, S₁₁ < -10 dB, from 0.8 GHz up to 10 GHz; moreover, the EBG inclusions increase the front to back ratio to provide the gains of -10 dBi, -4 dBi, 0 dBi at 0.915 GHz, 1.88 GHz, and 2.45 GHz, respectively. Moreover, a SAR reduction is achieved up to 64% down after the EBG layer introduction. In addition, the antenna distortion effect in terms of group delay (G_d) after 3.1 GHz up to 10 GHz is tested; the maximum variation is found to be less than 1ns which shows a linear phase response with distortionless waveforms. Such a feature is found very suitable for UWB applications in modern wireless systems. The antenna performance improvement after introducing the proposed EBG defects is validated experimentally and numerically. The solar panel I-V characteristics are measured after the antenna structure introduction. Next, the solant RF port is connected to a rectifier circuit to realize the rectenna performance port that collects the RF energy at three bands in terms of efficiency spectra. Finally, it is proofed that the proposed Solant-Rectenna offers an excellent, compacted, and flexible candidate for the wearable self-powered devices at different bands.

1. Balanis, C. A., Antenna Theory: Analysis and Design, 3rd Ed., John Wiley & Sons Press, 2005.

2. Al-Janabi, M. A. and S. K. Kayhan, "Flexible vivaldi antenna based on a fractal design for RF-energy harvesting," Progress In Electromagnetics Research M, Vol. 97, 177-188, 2020.
doi:10.2528/PIERM20073003

3. Shafique, K., B. A. Khawaja, M. D. Khurram, et al. "Energy harvesting using a low-cost rectenna for Internet of Things (IoT) applications," IEEE Access, Vol. 6, 30932-30941, 2018.
doi:10.1109/ACCESS.2018.2834392

4. Elwi, T. A., "Printed microwave metamaterial-antenna circuitries on nickel oxide polymerized palm fiber substrates," Nat. Sci. Rep., Vol. 9, No. 2174, 1-14, 2019.

5. Elwi, T. A., "Novel UWB printed metamaterial microstrip antenna based organic substrates for RF-energy harvesting applications," Inter. Jour. of Elect. & Comm., Vol. 101, No. 9, 1-10, 2019.

6. Elwi, T. A. and B. A. Ahmed, "A fractal metamaterial based printed dipoles on a nickel oxide polymer palm fiber substrate for Wi-Fi applications," Inter. Jour. of Elect. & Comm., Vol. 96, No. 23, 122-129, 2018.
doi:10.1016/j.aeue.2018.09.020

7. Hatem, G. M., A. J. Salim, T. A. Elwi, et al. "Wunderlich curve fractal dipole antenna for dual-band wearable RFID applications," Jou. Eng. and App. Scie., Vol. 14, No. 4, 1093-1099, 2019.
doi:10.36478/jeasci.2019.1093.1099

8. Zeng, M., Z. Li, A. S. Andrenko, Y. Zeng, and H. Z. Tan, "A compact dual-band rectenna for GSM900 and GSM1800 energy harvesting," International Journal of Antennas and Propagation, Vol. 2018, Article ID 4781465, 9 pages, 2018.

9. Elwi, T. A., A. I. Imran, and Y. Alnaiemy, "A miniaturized lotus shaped microstrip antenna loaded with EBG structures for high gain-bandwidth product applications," Progress In Electromagnetics Research C, Vol. 60, 157-167, 2015.
doi:10.2528/PIERC15101804

10. Elwi, T. A., "A slotted lotus-shaped microstrip antenna based EBG structures," Wirel. Comm. Tech., Vol. 2, No. 1, 1-24, 2018.

11. Imran, A. I. and T. A. Elwi, "A cylindrical wideband slotted patch antenna loaded with frequency selective surface for MRI applications," Eng. Sci. & Tech., an Int. Jou., Vol. 20, No. 3, 990-996, 2017.
doi:10.1016/j.jestch.2017.04.001

12. Nguyen, N. H., T. D. Bui, and A. D. Le, "A novel wideband circularly polarized antenna for RF energy harvesting in wireless sensor nodes," International Journal of Antennas and Propagation, Vol. 2018, Article ID 1692018, 9 pages, 2018.

13. Anguera, J., C. Puente, E. Martínez, et al. "The fractal Hilbert monopole: A two-dimensional wire," Micr. & Opt. Tech. Lett., Vol. 36, No. 2, 102-104, 2003.
doi:10.1002/mop.10687

14. Gala, D., J. Soler, C. Puente, et al. "Miniature microstrip patch antenna loaded with a space-filling line based on the fractal Hilbert curve," Micr. & Opt. Tech. Lett., Vol. 38, No. 4, 311-312, 2003.
doi:10.1002/mop.11046

15. Azad, M. Z. and M. Ali, "A miniaturized Hilbert PIFA for dual-band mobile wireless applications," IEEE Ant. & Wire. Prop. Lett., Vol. 4, No. 3, 59-62, 2005.
doi:10.1109/LAWP.2005.844128

16. Azaro, R., F. Viani, L. Lizzi, et al. "A monopolar quad-band antenna based on a Hilbert self-affine prefractal geometry," IEEE Ant. & Wire. Prop. Lett., Vol. 8, No. 5, 177-180, 2009.
doi:10.1109/LAWP.2008.2001428

17. Puente, C., E. Rozan, and J. Anguera, "Space-filling miniature antennas,", US Pat. 2000, 7,202,822.

18. Mathur, R. and S. Dwari, "Compact planar reconfigurable UWB-MIMO antenna with on-demand worldwide interoperability for microwave access/wireless local area network rejection," IET Microw. Antennas Propag., Vol. 13, 1684-1689, 2019.
doi:10.1049/iet-map.2018.6048

19. Elwi, T. A., Z. A. Al-Hussain, and O. Tawfeeq, "A Hilbert metamaterial printed antenna based on organic substrates for energy harvesting," IET Micr., Ant. & Prop., Vol. 10, No. 2, 1-8, 2019.

20. Vaccaro, S., C. Pereira, J. R. Mosig, et al. "In-flight experiment for combined planar antennas and solar cells (SOLANT)," IET Micr., Ant. & Prop., Vol. 3, No. 8, 1279-1287, 2009.
doi:10.1049/iet-map.2008.0410

21. Vaccaro, S., P. Torres, J. R. Mosig, et al. "Stainless steel slot antenna with integrated solar cells," Electron. Lett., Vol. 36, No. 25, 2059-2060, 2000.
doi:10.1049/el:20001467

22. Al-Adhami, Y. and E. Ercelebi, "A plasmonic monopole antenna array on flexible photovoltaic panels for further use of the green energy harvesting," Progress In Electromagnetics Research M, Vol. 68, 143-152, 2018.
doi:10.2528/PIERM18032104

23. CSTMWS, http://www.cst.com, April 2019.

24. Vaccaro, S., J. R. Mosig, and P. Maagt, "Two advanced solar antenna ``SOLANT'' designs for satellite and terrestrial communications," IEEE Tran. on Ant. & Prop., Vol. 51, No. 8, 110-116, 2003.

25. Al-Adhami, Y. and E. Ercelebi, "Plasmonic metamaterial dipole antenna array circuitry based on flexible solar cell panel for selfpowered wireless systems," Micr. and Opt. Tech. Lett., Vol. 59, No. 9, 2365-2371, 2017.
doi:10.1002/mop.30747

26. HFSS, http://www.ansoft.com, April 2019.

27. https://www.powercastco.com/documentation/p21xxcsr-evb-datasheet/.

28. Elwi, T. A., D. A. Jassim, and H. H. Mohammed, "Novel miniaturized folded UWB microstrip antenna-based metamaterial for RF energy harvesting," Int. J. Commun. Syst., Vol. 1, No. e4305, 1-15, 2020.

29. Okba, A., A. Takacs, and H. Aubert, "Compact flat dipole rectenna for IoT applications," Progress In Electromagnetics Research C, Vol. 87, 39-49, 2018.
doi:10.2528/PIERC18071604

Dr. Ahmed Imad Imran

Prof. Taha Ahmed Elwi

Dr. Ali J. Salim