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:
Jan. 23, 2018
Filed:
Feb. 24, 2015
Hitachi Kokusai Electric Inc., Tokyo, JP;
Manabu Nakamura, Tokyo, JP;
Naoya Fujimoto, Tokyo, JP;
Norikazu Kato, Tokyo, JP;
Yoshiyuki Oshida, Tokyo, JP;
Naoto Takahashi, Tokyo, JP;
HITACHI KOKUSAI ELECTRIC INC., Tokyo, JP;
Abstract
A matching unit includes a directional coupler for detecting a travelling wave and a reflected wave; a matching circuit including a first variable capacitance capacitor, a second variable capacitance capacitor and an inductance; and a control unit for controlling VCand VCof the first and the second variable capacitance capacitor by calculating a reflection coefficient based on the travelling wave and the reflected wave. When a distance between the calculated reflection coefficient and a circle described by a trace of the reflection coefficient which passes through a matching point on a Smith chart is greater than a predetermined value, the control unit changes VCof the second variable capacitance capacitor and the calculated reflection coefficient to make the distance within the predetermined value. When the distance becomes within the predetermined value, the control unit changes VCof the first variable capacitance capacitor and makes the calculated reflection coefficient smaller.