Image Recovery Millimeter-Wave Mixer

Abstract

This paper describes the design of an 80 GHz image recovery mixer that has a conversion loss of 4.4 dB. The image filter is a circular highpass filter using the cutoff properties of a waveguide section with reduced diameter. LO injection is preformed by a TE111-mode bandpass filter. The mixer noise temperature is 650 K at room temperature and 280 K at 20 K. The lower sideband suppression is better than 40 dB.