Design of a ultra-compact low-power rectenna in paper substrate for energy harvesting in the Wi-Fi band

This paper presents the design of a novel rectenna based on a tapered annular slot and a single-diode rectifier, optimized to operate in the Wi-Fi band and in presence of low input power (P
_avs
=-15 dBm). In order to obtain a compact layout a double-layer architecture has been considered, according to which the interior metal surface of the annular slot is employed as ground plane for the rectifying circuit placed on the other side of the substrate. As a result, a rectenna with an active area of only 40 × 33 mm
²
and an efficiency included between 26.5 and 28% has been obtained. The antenna has been fabricated in paper substrate and tested in the anechoic chamber. Then, the rectifier has been designed and optimized within the Advanced Design System suite. Finally, the rectenna performance has been discussed and compared to the State of the Art (SoA).