Title:
ANTENNA DEVICE
Document Type and Number:
WIPO Patent Application WO/2012/066838
Kind Code:
A1
Abstract:
Maintain a stable antenna characteristic at all times, detecting a surrounding environment of the antenna which changes the antenna characteristic and correcting the antenna characteristic as appropriate, without disposing a special conductor for detecting the surrounding environment. A variable matching circuit (31) is disposed between a first antenna element electrode (21) and a feeder circuit (41). A reactance element (X1) and a matching circuit (32) are disposed between a second antenna element electrode (22) and a feeder circuit (42). Additionally, a reactance element (X2), a capacitance detector circuit (60), and a matching control circuit (70) are disposed between the second antenna element electrode (22) and the variable matching circuit (31). The capacitance detector circuit (60) converts a change in floating capacitance arising from the approach of a person, etc., into a voltage value change and outputs same. The matching control circuit (70) controls the variable matching circuit (31) according to the output signal of the capacitance detector circuit (60).
Inventors:
NAGUMO SHOJI (JP)
Application Number:
PCT/JP2011/069684
Publication Date:
May 24, 2012
Filing Date:
August 31, 2011
Export Citation:
Assignee:
MURATA MANUFACTURING CO (JP)
NAGUMO SHOJI (JP)
NAGUMO SHOJI (JP)
International Classes:
H01Q1/50; H01Q1/24; H01Q5/10; H01Q5/335; H01Q5/40; H01Q9/16; H01Q21/28; H03H7/38; H04B1/40
Domestic Patent References:
| WO2011024506A1 | 2011-03-03 |
Foreign References:
| JP2004312157A | 2004-11-04 | |||
| JP2009290275A | 2009-12-10 | |||
| JP2000286924A | 2000-10-13 | |||
| JP2009290454A | 2009-12-10 |
Attorney, Agent or Firm:
Kaede Patent Attorneys' Office (JP)
Patent business corporation Kaede Patent Attorneys' Office (JP)
Patent business corporation Kaede Patent Attorneys' Office (JP)
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