Due to low power density, it is difficult for a single-band rectenna to harvest enough power for IoT devices like wireless sensors. Thus to supply these consuming devices, harvesting RF energy from multiple frequencies is a solution to enhance the amount of harvested DC power. In this work, we introduce a triple-band rectenna, working at 900 MHz, 1.8 GHz and 2.1 GHz, three readily available bands in the ambience, for energy harvesting application. The proposed rectenna consists of three monoband rectifiers connected to a multi-band receiving antenna via a highly efficient triplexer. The antenna is made by superposing two concentric rings and manipulating their radii to achieve the desirable operating frequencies, with antenna gains of respectively 2.5 dBi, 4.5 dBi, and 4 dBi. The contiguous triplexer is made by connecting open stubs band-reject filters and optimizing their positions, resulting in the triplexing efficiency higher than 75%. The measured RF-DC efficiency under -10 dBm triple-tone input power is 40%.
2. Nguyen, N., Q. C. Nguyen, and M. T. Le, "A novel autonomous wireless sensor node for IoT applications," TELKOMNIKA Telecommun. Comput. Electron. Control, Vol. 17, No. 5, 2389, Oct. 2019.
3. Nguyen, T. H., et al., "Smart shoe based on battery-free Bluetooth low energy sensor," Industrial Networks and Intelligent Systems, N.-S. Vo, V.-P. Hoang, and Q.-T. Vien, Eds., Vol. 379, 156-166, Springer International Publishing, Cham, 2021.
4. Cansiz, M., D. Altinel, and G. K. Kurt, "Efficiency in RF energy harvesting systems: A comprehensive review," Energy, Vol. 174, 292-309, May 2019.
5. Pinuela, M., P. D. Mitcheson, and S. Lucyszyn, "Ambient RF energy harvesting in urban and semi-urban environments," IEEE Trans. Microw. Theory Tech., Vol. 61, No. 7, 2715-2726, Jul. 2013.
6. Chandrasekaran, K. T., K. Agarwal, Nasimuddin, A. Alphones, R. Mittra, and M. F. Karim, "Compact dual-band metamaterial-based high-efficiency rectenna: An application for ambient electromagnetic energy harvesting," IEEE Antennas Propag. Mag., Vol. 62, No. 3, 18-29, Jun. 2020.
7. Shen, S., C.-Y. Chiu, and R. D. Murch, "A dual-port triple-band L-probe microstrip patch rectenna for ambient RF energy harvesting," IEEE Antennas Wirel. Propag. Lett., Vol. 16, 3071-3074, 2017.
8. Mansour, M. M. and H. Kanaya, "Compact and broadband RF rectifier with 1.5 octave bandwidth based on a simple pair of L-section matching network," IEEE Microw. Wirel. Compon. Lett., Vol. 28, No. 4, 335-337, Apr. 2018.
9. Daskalakis, S. N., A. Georgiadis, A. Collado, and M. M. Tentzeris, "An UHF rectifier with 100% bandwidth based on a ladder LC impedance matching network," 2017 12th European Microwave Integrated Circuits Conference (EuMIC), 411-414, Nuremberg, Oct. 2017.
10. Gorur, A. K. and C. Karpuz, "A novel microstrip triplexer based on meandered loop resonators," 2017 IEEE Asia Pacific Microwave Conference (APMC), 1242-1245, Kuala Lumpar, Nov. 2017.
11. Tang, C.-W. and C.-T. Tseng, "Design of a packaged microstrip triplexer with star-junction topology," 2012 42nd European Microwave Conference, 459-462, Amsterdam, Oct. 2012.
12. Chen, C.-F., T.-Y. Huang, T.-M. Shen, and R.-B. Wu, "A miniaturized microstrip common resonator triplexer without extra matching network," 2006 Asia-Pacific Microwave Conference, 1439-1442, Yokohama, Japan, Dec. 2006.
13. Elwi, T. A., Z. A. Abdul Hassain, and O. A. Tawfeeq, "Hilbert metamaterial printed antenna based on organic substrates for energy harvesting," IET Microw. Antennas Propag., Vol. 13, No. 12, 2185-2192, Oct. 2019.
14. Elwi, T. A. and S. G. Abdulqader, "Further investigation on solant-rectenna-based flexible Hilbert-shaped metamaterials," IET Nanodielectrics, Vol. 3, No. 3, 88-93, Sep. 2020.
15. Elwi, T. A. and A. M. Al-Saegh, "Further realization of a flexible metamaterial-based antenna on indium nickel oxide polymerized palm fiber substrates for RF energy harvesting," Int. J. Microw. Wirel. Technol., Vol. 13, No. 1, 67-75, Feb. 2021.
16. Elwi, T. A., "Novel UWB printed metamaterial microstrip antenna based organic substrates for RF-energy harvesting applications," AEU - Int. J. Electron. Commun., Vol. 101, 44-53, Mar. 2019.
17. Al-Dulaimi, Z., T. A. Elwi, D. C. Atilla, and C. Aydin, "Design of fractal based monopole antenna array with ultra-mutual coupling reduction for MIMO applications," 2018 18th Mediterranean Microwave Symposium (MMS), 39-42, Istanbul, Oct. 2018.
18. Pandey, R., A. K. Shankhwar, and A. Singh, "Design, analysis, and optimization of dual side printed multiband antenna for RF energy harvesting applications," Progress In Electromagnetics Research C, Vol. 102, 79-91, 2020.
19. Deng, P.-H., M.-I. Lai, S.-K. Jeng, and C. H. Chen, "Design of matching circuits for microstrip triplexers based on stepped-impedance resonators," IEEE Trans. Microw. Theory Tech., Vol. 54, No. 12, 4185-4192, Dec. 2006.
20. El-Tokhy, A., R. Wu, and Y. Wang, "Microstrip triplexer using a common triple-mode resonator," Microw. Opt. Technol. Lett., Vol. 60, No. 7, 1815-1820, Jul. 2018.
21. Hemour, S., et al., "Towards low-power high-efficiency RF and microwave energy harvesting," IEEE Trans. Microw. Theory Tech., Vol. 62, No. 4, 965-976, Apr. 2014.
22. Mattsson, M., C. I. Kolitsidas, and B. L. G. Jonsson, "Dual-band dual-polarized full-wave rectenna based on differential field sampling," IEEE Antennas Wirel. Propag. Lett., Vol. 17, No. 6, 956-959, Jun. 2018.
23. Khemar, A., A. Kacha, H. Takhedmit, and G. Abib, "Design and experiments of a dual-band rectenna for ambient RF energy harvesting in urban environments," IET Microw. Antennas Propag., Vol. 12, No. 1, 49-55, Jan. 2018.
24. Boursianis, A. D., et al., "Triple-band single-layer rectenna for outdoor RF energy harvesting applications," Sensors, Vol. 21, No. 10, 3460, May 2021.
25. Balanis, C. A., Antenna Theory: Analysis and Design, 4th Ed., Wiley, Hoboken, New Jersey, 2016.