Title:
An impedance match change circuit, an antenna system, and a communication terminal device
Document Type and Number:
Japanese Patent JP5910779
Kind Code:
B2
Abstract:
An antenna device includes an impedance-matching switching circuit connected to a feeding circuit, and a radiating element. The impedance-matching switching circuit matches the impedance of the radiating element as a second high frequency circuit element and the impedance of the feeding circuit as a first high frequency circuit element. The impedance-matching switching circuit includes a transformer matching circuit and a series active circuit. The transformer matching circuit matches the real parts of the impedance and matches the imaginary parts of the impedance in the series active circuit. Thus, impedance matching is performed over a wide frequency band at a point at which high frequency circuits or elements having different impedances are connected to each other.
More Like This:
Inventors:
Kenichi Ishizuka
Ueki travelogue
Tokiko Kato
Koji Shiraki
Ueki travelogue
Tokiko Kato
Koji Shiraki
Application Number:
JP2015085707A
Publication Date:
April 27, 2016
Filing Date:
April 20, 2015
Export Citation:
Assignee:
MURATA MANUFACTURING CO.,LTD.
International Classes:
H03H7/38; H04B1/04; H04B1/18; H04B1/40
Domestic Patent References:
| JP53015039A | ||||
| JP51033916A | ||||
| JP2011061662A |
Foreign References:
| US6664935 | ||||
| US20070138908 |
Attorney, Agent or Firm:
Kaede International Patent Office
Previous Patent: A paper container which consists of a packaging material and it
Next Patent: DISCONTINUITY DETECTOR FOR GLOW PLUG
Next Patent: DISCONTINUITY DETECTOR FOR GLOW PLUG