Millimeter wave image guide integrated balanced mixer

Claim 1

A millimeter image waveguide balanced mixer integrated circuit adapted to be powered from a source of electrical power and coupled to IF amplifier means, comprising in combination: a metal substrate having a conductive surface defining an image plane; two adjacent lengths of image guide consisting of dielectric material having a relatively low propagation loss to millimeter wave signals applied thereto and including a layer of metallization on one surface thereof which is bonded to said conductive surface, said length of image waveguides having an intermediate signal coupling region consisting of a slot type of separation of predetermined length and width to provide a signal couplng region; image waveguide to metal waveguide transition means consisting of a portion of said conductive surface and a metal body having a pair of rectangular or cross-sectional channels formed in one surface thereof which is secured to said conductive surface to form a pair of hollow metal waveguide sections providing first and second signal ports, are respectively adapted to receive an input signal and a local oscillator signal and wherein like end portions of said two lengths of image guide are respectively tapered and located inside of said metal waveguide sections; a cavity structure consisting of a metallized body of dielectric material and including a layer of metallization on one surface which is bonded to said conductive surface, said body including two separate cavities, each having metallized outer surfaces and an opening adapted to respectively receive like opposite end portions of said two lengths of image guide and respectively including decoupling slots on either side of said image guide for decoupling the image guides from the respective cavities, said end portions additionally having conductor line patterns formed on the upper surface of the respective image guides opposite said one surface for coupling IF signals away from said cavities; an active millimeter wave mixer device located in each of said cavities and including means for being coupled to said source of electrical power and being coupled to said line pattern of the respective image guide for coupling IF signals thereto; and means coupling IF signals from said respective line patterns to said IF amplifier.