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:
Jul. 16, 2019
Filed:
Jun. 08, 2017
Murata Manufacturing Co., Ltd., Kyoto, JP;
Manabu Nakahori, Kyoto, JP;
Masakazu Tani, Kyoto, JP;
MURATA MANUFACTURING CO., LTD., Kyoto, JP;
Abstract
A variable filter circuit includes: a series arm connected in series between a signal input terminal and a signal output terminal; a parallel arm connected between the series arm and a ground terminal that has a resonator; and a variable reactance portion in the parallel arm, and the resonator of a parallel arm at an initial stage connected to the signal input terminal that has a resonant frequency fr and an anti-resonant frequency fa that satisfy 100×(fn−fr)/(fa−fr)≤23.9(%) for communication bands for each of which a stop band is set so as to be close to a high-frequency side of a pass band, among the plurality of communication bands, where a resonant frequency is fr, an anti-resonant frequency is fa, and a cutoff frequency at a high-frequency side of a pass band of each communication band is fn.