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:
Feb. 18, 2003
Filed:
Apr. 19, 2001
Yasuo Yamada, Kanazawa, JP;
Kikuo Tsunoda, Mishima-gun, JP;
Masayuki Atokawa, Kanazawa, JP;
Hirofumi Miyamoto, Kanazawa, JP;
Hajime Suemasa, Nomi-gun, JP;
Abstract
A frequency variable filter in which both the frequency of an attenuation pole and the attenuation bandwidth can be varied. In the frequency variable filter, two serial resonance sections composed of resonators and resonance capacitors are electrically connected to each other via a capacitor. The respective resonator in each of the serial resonance sections is electrically connected in parallel with a corresponding serial circuit composed of a frequency shifting capacitor and a PIN diode. A coupling capacitor electrically connects the junctions defined respectively between the frequency shifting capacitor and the PIN diode in each of the serial circuits.