24 GHz substrate integrated waveguide (SIW) rectenna for energy harvesting and wireless power transmission

A novel substrate integrated waveguide (SIW) rectenna operating at 24 GHz is presented. Rectennas find application in wireless power transmission and energy harvesting systems. Millimeter wave rectennas allow for compact structures and large array implementations. Furthermore, SIW technology is particularly suitable for millimeter wave systems due to increased isolation, and reduced radiation leakage and losses. A compact rectenna integrating a patch radiator and a Schottky diode within a SIW resonator is proposed. The antenna is designed using a finite element based electromagnetic simulator, while the rectenna is optimized using harmonic balance analysis. The obtained efficiency is comparable to reported values in the literature for available input power levels below 10 mW. A prototype is fabricated and characterized showing that SIW technology can be used to obtain very compact rectenna elements that can be used in the implementation of large arrays of rectennas.