Compact 5.8-GHz Rectenna Using Stepped-Impedance Dipole Antenna

This letter describes a compact 5.8-GHz rectenna using a stepped-impedance dipole antenna. In comparison to the conventional uniform half-wavelength dipole antenna, the stepped-impedance dipole antenna shows a 23% length reduction. This stepped-impedance dipole antenna is then used to receive the microwave power for a rectenna. The rectenna shows a maximum conversion efficiency of 76% at 5.8 GHz with a load resistance of 250 Omega. Furthermore, the conversion efficiency is better than 67% from 5.725 to 5.875 GHz, which covers the entire 5.8-GHz ISM band.