Design of 94GHz High Efficiency Rectifier MMIC

This paper presents a 94 GHz band high-efficiency rectifier MMIC using a GaAs Schottky diode. The diode used here is a commercial Schottky diode with a cutoff frequency of 3 THz. The proposed circuit employs a single shunt topology, and consists of a DC block, an input matching circuit, the diode, and a band stop filter. In the input matching circuit, an open stub is connected at a quarter-wave length of the fundamental frequency far from the diode cathode end. That configuration effectively improves the diode performances. The band stop filter at the DC output side consists of radial stubs to suppress fundamental and second harmonic frequency signals and a high-frequency cutoff inductor. To optimize their respective phases, the filter effectively returns the fundamental and second harmonic signals to a diode. The proposed rectifier MMIC achieves an RF-DC conversion efficiency of 49.7% at an input power of 15 dBm 94 GHz.