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:
Mar. 15, 1988
Filed:
Feb. 10, 1986
Hiroyuki Mizukami, Yokohama, JP;
Masaki Noda, Yokohama, JP;
Toshio Nagashima, Yokohama, JP;
Keiro Shinkawa, Yokohama, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A frequency converter which is capable of rejecting unnecessary signals generated by image signals. The frequency converter has first and second local oscillation circuits which generate local oscillation signals whose frequencies are the same and whose phases are different by 90 degrees from each other. The converter further includes two mixer circuits, and a hybrid coupler. The mixer circuits generate two unnecessary signals whose phases are different by 90 degrees from each other. The hybrid coupler delays one unnecessary signal by a quarter of a wavelength to generate two unnecessary signals whose phases are different by 180 degrees from each other, so that they are cancelled by each other.