Flexible 2-gram rectenna with 50% conversion efficiency at very low incident power densities

This paper presents a 900MHz flexible folded dipole rectenna with 2.7 dB RF-to-DC conversion loss and mass of only 2 grams. It employs a Schottky diode, a capacitor, and printed coplanar circuit elements. Rectification efficiency is improved by harmonic terminations resulting in class-F waveform shaping achieving an estimated efficiency of 53% efficiency AT 8uW/cm
²
incident power density. The rectenna is printed on 0.13mm PET with a commercial printing process depositing 1-µm-thick conductive traces.