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:
Aug. 19, 1997
Filed:
Sep. 27, 1995
Kazuaki Takahashi, Kawasaki, JP;
Munenori Fujimura, Kawasaki, JP;
Hiroyuki Yabuki, Kawasaki, JP;
Mitsuo Makimoto, Yokohama, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A strip dual mode filter includes a strip line ring resonator having a uniform line impedance and an electric length equivalent to a wavelength of a microwave, an input terminal coupled to a point A of the ring resonator, a feed-back circuit connected to points C and D and arranged in a central hollow space of the ring resonator and an output terminal coupled to a point B of the ring resonator. The points A to D are spaced by a quarter-wave length of the microwave in that order. The microwave input to the point A is resonated in the ring resonator in a first mode and is input to the feed-back circuit from the point C. Therefore, a phase of the microwave shifts by a multiple of a half-wave length of the microwave, and the microwave is output to the point D. Thereafter, the microwave is resonated in the ring resonator in a second mode orthogonal to the first mode and is output from the point B to the output terminal. Therefore, the microwave can be resonated and filtered in two orthogonal modes in the strip dual mode filter.