high-efficiency rectenna element has been designed
and tested at 5.8 GHz for applications involving microwavepower
transmission. The dipole antenna and filtering circuitry
are printed on a thin duroid substrate. A silicon Schottkybarrier
mixer diode with a low breakdown voltage is used
as the rectifying device. The rectenna element is tested inside
a waveguide simulator and achieves an RF-to-dc conversion
efficiency of 82% at an input power level of 50-mW and 327-
load. Closed-form equations are given for the diode efficiency and
input impedance as a function of input RF power. Measured and
calculated efficiency results are in good agreement. The antenna
and circuit design are based on a full-wave electromagnetic
simulator. Second harmonic power levels are 21 dB down from
the fundamental input power.
Index Terms—Detectors, nonlinear circuits,
