2022 年 15 巻 p. E21-016-1-E21-016-7
This paper describes a gamma-matched textile rectenna structure that is suitable for batteryless wearable accessories powered by microwaves using a conductive-yarn antenna. The proposed structure consists of a slidable button-shaped rectifier module with LED that allows the antenna to pass through its metal holes, thus making it possible to connect a soft textile antenna with a hard rectifier module to easily perform impedance matching by sliding the module on the antenna, while watching luminance of the LED light. To verify the effectiveness of our textile rectenna structure, we fabricated a button-shaped rectifier module 7.5 mm in diameter including an LED and a 6-cm-long bundled conductive-yarn antenna consisting of 0.5-mm-thick single yarns. The experimental results showed that, for 2.45-GHz wireless power transmission with an average transmitted power of 1 W, the LED on the rectifier module blinked while dissipating power of 0.355 mW at a distance of 70 cm from the wireless transmitter. We also fabricated a friendship bracelet and a pair of embroidered socks equipped with our rectenna as LED textile accessories.
