A Novel Single-Diode Microwave Rectifier With a Series Band-Stop Structure

A single-diode compact microwave rectifier with a series band-stop structure is presented in this paper. The bandstop structure is connected to the diode in series to block the harmonics produced during rectifying. It replaces the cascading bandpass or low-pass filter between the input and the diode in a conventional microwave rectifier. A microwave rectifier at 2.45 GHz with an HSMS 282 Schottky diode is realized based on the proposed design method. A short-ended eighthwavelength microstrip transmission line is applied to the rectifier in series with the diode as a band-stop structure. The short-ended microstrip transmission line presents an inductive impedance to compensate the diode capacitive impedance at fundamental frequency and turns to an open circuit to block the second harmonic for power recycling. The proposed circuit shows a novel schematic for compact microwave rectifiers. The fabricated rectifier is compact with a dimension of 0.15λg × 0.2λg. A microwave-to-dc conversion efficiency of 80.9% is achieved at 20 dBm input power with a 580-Ω dc load.