A 10-110 GHz fundamental/harmonic rat-race mixer

Abstract

This paper describes a broadband 10-110GHz mm-wave rat-race ring diode mixer. The mixer can be used as a fundamental mixer as well as a harmonic mixer. The finite-ground-width CPW on a 15mil alumina substrate is used to implement the circuit. The mixer is designed to allow DC bias that a local power as low as 0dBm could properly pump the mixer. Two commercial available M/A-Com MA4E2037 GaAs beam-leaded Schottky diodes are used. The measured conversion loss is typically 9dB from 10 to 100GRz in the fundamental mixing mode and 15dB from 20 to 110GRz in the harmonic mixing mode.