Design and modeling of a wearable textile rectenna array implemented on Cordura fabric for batteryless applications

Abstract

This paper presents a wearable rectenna array fabricated using Cordura textile material for harvesting low-power radio frequency (RF) energy. The dielectric properties of the textile were thoroughly investigated for circuit and antenna design. The rectenna element comprises a linearly polarized patch antenna and a single-stage full-wave Greinacher rectifier. The proposed stack topology helps reduce the size of the elements in the rectenna array. An RF choke is added to the array to prevent impedance mismatch due to changes in load impedance, and a foam with a shielding ground is inserted between the rectifier circuit and the human body to eliminate the body-proximity effect. A maximum output voltage of 1.05 V is achieved when the 2 × 2 rectenna array attached to a human body and 150 cm from the indoor Wi-Fi access point whose output power is 20 dBm and the antenna gain is 5 dBi.

KEYWORDS:

• Ambient RF power harvesting
• battery-free
• energy harvesting
• rectenna
• textile rectenna
• wireless power
• wearable

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by Ministry of Science and Technology: [grant number 105-2221-E-197-001-,106-2221-E-032-013-].

Notes on contributors

Yu-Jen Chi

Yu-Jen Chi was born in Taipei, Taiwan, R.O.C., in 1985. He received his BS and MS degrees in Electronic Engineering from National Ilan University, I-Lan, Taiwan, R.O.C., in 2007 and 2009, respectively, and the PhD degree in Electrical Engineering from National Chiao Tung University, Hsinchu, Taiwan, R.O.C., in 2014. After graduation, he joined as faculty at Tamkang University, New Taipei City, Taiwan, in 2014, where he is currently an Assistant Professor of Electrical and Computer Engineering. His main research interests are in multiband antennas for mobile devices, reconfiguralbe antennas, millimeter-wave antennas, metamaterials, and antennas for biomedical applications. Dr Chi was the recipient of the Best Poster Award in the 2009 IEEE International Workshop on Antenna Technology (iWAT 2009).

Chih-His Lin

Chih-His Lin was born in Keelung City, Taiwan, R.O.C., in 1993. He received his MS degree in electronic engineering from National Ilan University, Ilan, Taiwan, R.O.C., in 2018. He is currently an RF engineering in the Sinbon Electronics Co. Ltd, Taiwan. His research interests include wireless power transfer, wearable RFID antenna, and antenna design.

Chien-Wen Chiu

Chien-Wen Chiu was born in Maoli, Taiwan, R.O.C., in 1962. He received his BS degree from National Taiwan Normal University, Taipei, Taiwan in 1984, and his MS and PhD degrees in electrical engineering from National Taiwan University, Taipei, Taiwan, R.O.C., in 1990 and 1996, respectively. He is currently a Professor and the chairman of the Electronic Engineering Department, National Ilan University in Ilan City, Taiwan. Prof Chiu’s research focuses on IoT applications, mobile antenna design, wearable RFID antenna, and wireless power transfer.