FREQUENCY-VARIABLE ANTENNA AND COMMUNICATION DEVICE HAVING THE SAME

Title:

FREQUENCY-VARIABLE ANTENNA AND COMMUNICATION DEVICE HAVING THE SAME

Document Type and Number:

WIPO Patent Application WO/2004/109850

Kind Code:

A1

Abstract:

A radiation electrode (2), which acts as a monopole antenna, is shaped in such a loop that an open end (2K) of the radiation electrode (2) is opposed to a power supply end (2Q) thereof with a spacing therebetween. A frequency-variable circuit (3) is provided on the loop path of the radiation electrode (2). The frequency-variable circuit (3), which has a reactance component and a portion capable of varying the reactance component, uses the variable reactance component to vary the electrical length of the radiation electrode (2), thereby varying the resonance frequency of the radiation electrode (2). The provision of the frequency-variable circuit (3) on the loop path of the radiation electrode (2) can vary the resonance frequency of the radiation electrode (2), while maintaining an excellent matching between the radiation electrode (2) and the circuit side of a communication device (i.e., suppressing the degradation of the gain). The variability of the resonance frequency of the radiation electrode (2) in accordance with a frequency required for a communication allows the frequency-variable antenna (1) to have a wider bandwidth than the radiation electrode (2) itself.

More Like This:

WO/2022/250310	ANTENNA MODULE AND ELECTRONIC DEVICE COMPRISING SAME
JP2020078054	HEARING DEVICE WITH ANTENNA EXTENDING FROM THE SAME
JP4010782	Wireless terminal device and its reception operation control program

Inventors:

YUASA ATSUYUKI (JP)
IKUSHIMA MIE (JP)
IZAWA MASAHIRO (JP)
KAWAHATA KAZUNARI (JP)

Application Number:

PCT/JP2004/005646

Publication Date:

December 16, 2004

Filing Date:

April 20, 2004

Export Citation:

Click for automatic bibliography generation Help

Assignee:

MURATA MANUFACTURING CO (JP)
YUASA ATSUYUKI (JP)
IKUSHIMA MIE (JP)
IZAWA MASAHIRO (JP)
KAWAHATA KAZUNARI (JP)

International Classes:

H01Q1/24; H01Q9/04; (IPC1-7): H01Q1/38; H01Q1/24; H01Q9/30; H01Q21/28

Foreign References:

JPH10173427A	1998-06-26
JP2000156607A	2000-06-06
JPH1131913A	1999-02-02
JP3206825B2	2001-09-10
JP2001267826A	2001-09-28
JP2003142928A	2003-05-16
JP2002246837A	2002-08-30
JP2001068917A	2001-03-16
JPH0621711A	1994-01-28

Attorney, Agent or Firm:

Igarashi, Kiyoshi (Yokohamahigashiguchi Bldg. 10-13, Takashima 2-chome, Nishi-k, Yokohama-shi Kanagawa, JP)

Download PDF:

View/Download PDF PDF Help

Previous Patent: ANTENNA FOR A FOLDABLE RADIO DEVICE

Next Patent: MONOLITHIC MILLMETER WAVE REFLECT ARRAY SYSTEM