High efficiency MW-band rectenna using a coaxial dielectric resonator and distributed capacitors

This paper presents experimental studies on the improvement of RF-DC conversion efficiency of the rectenna using a high Q λ/4-coaxial dielectric resonator and distributed capacitors at 850 MHz. The conventional rectenna using an LC resonator has ohmic and dielectric losses due to a shunt capacitor. In order to eliminate these losses, it is effective to disperse current by using distributed capacitors, such as a film capacitor. To achieve an ultimate efficiency, we have constructed a rectenna using both a coaxial dielectric resonator and a film capacitor. Using the developed rectenna, charge-up experiments to supply power to a super-capacitor at an input power of -10 dBm were performed and its ability to achieve a long-life operation of an LCD clock device was confirmed.