Title:
TUNING TYPE SLOT ANTENNA
Document Type and Number:
Japanese Patent JP3684285
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To vary the center frequency of impedance matching by connecting a variable capacitive element between the wall surface of a flat conductor box and a nearby point including an end of a belt-shaped conductor that is more distance away from the coupling part where the high frequency power is supplied and then varying the capacity value of the variable capacitive element.
SOLUTION: In regard to this coaxial resonation type slot antenna, a variable capacitive element 6 is provided on the upper face of a flat conductor box 1 and an island-shaped conductor 4 is provided on the surface of the box 1 to draw a coupling part 10 out of the box 1. The element 6 functions to add the capacity between the ground and a capacitive connection part 11 near an end of a belt-shaped conductor 3 that is more distant away from the part 10. Thereby, the density of the electric line of force increases at the part 11 compared with a case where not element 6 is connected, and the current density induced on the conductor 3 near the part 11 increases to compensate the increase of the density of the electric line of force. As a result, the resonance frequency, i.e., the impedance matching center frequency varies.
Inventors:
Takei Ken
Application Number:
JP5482597A
Publication Date:
August 17, 2005
Filing Date:
March 10, 1997
Export Citation:
Assignee:
株式会社日立製作所
International Classes:
H01Q1/24; H01Q13/10; H01Q23/00; (IPC1-7): H01Q13/10
Domestic Patent References:
| JP2065506A | ||||
| JP9074312A | ||||
| JP5034703U | ||||
| JP2101802A | ||||
| JP5029818A | ||||
| JP4213907A | ||||
| JP638578A | ||||
| JP61114604A | ||||
| JP32711U |
Attorney, Agent or Firm:
Katsuo Ogawa
Akio Takahashi
Akio Takahashi