The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 14, 1996
Filed:
Feb. 09, 1994
Edward C Niehenke, Baltimore, MD (US);
Marvin Cohn, Baltimore, MD (US);
Peter A Stenger, Woodbine, MD (US);
Westinghouse Electric Corporation, Pittsburgh, PA (US);
Abstract
A subharmonic image rejection and image enhancement mixer for mixing millimeter wavelength signals using a low conversion loss technique is described. A local oscillator frequency from an external source is fed to a first subharmonic mixer and through a phase shifter to a second subharmonic mixer. The phase shifter delays the local oscillator signal by (90.degree./n), where n is the multiple of the subharmonic mixers and is greater than 1. The first and second subharmonic mixers mix the local oscillator frequency with an input signal, which includes a desired frequency and an image frequency, to produce an intermediate frequency having a desired component and an image component at a select phase. A 0.degree.-90.degree. hybrid separates and terminates the image component of the intermediate frequency. The input port that feeds the input signal to each subharmonic mixer is dimensioned so as to provide a virtual image short termination or an image short termination to a self-generated image signal from each subharmonic mixer, thereby decreasing the conversion loss of the frequency mixer.