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:
Oct. 14, 2003
Filed:
Nov. 20, 2001
Hiroshi Iwai, Neyagawa, JP;
Atsushi Yamamoto, Osaka, JP;
Koichi Ogawa, Hirakata, JP;
Shinji Kamaeguchi, Kadoma, JP;
Tsukasa Takahashi, Kawasaki, JP;
Kenichi Yamada, Yokohama, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
An antenna is provided which can reconcile a low antenna resonance frequency and broadband frequency characteristics, while attaining stable impedance characteristics and enhanced design flexibility. A conductive plate is coupled to a conductive base plate via a first metal lead. A voltage is applied to the conductive plate from a supply point via a second metal lead. A conductive wall is electrically coupled to the conductive plate at one end thereof. An electromagnetic field coupling adjustment plate is electrically coupled to the other end of the conductive wall. The electromagnetic field coupling adjustment plate is disposed so as to leave a predetermined interspace between itself and the conductive base plate, thereby creating a capacitor in conjunction with the conductive base plate. The conductive wall and the electromagnetic field coupling adjustment plate are disposed so as to maximize a path length from a shot-circuiting portion (at which the conductive plate is coupled to the first metal lead) to an open end of the electromagnetic field coupling adjustment plate. Preferably, a current path extending from a supply portion (at which the conductive plate is coupled to the second metal lead) to the short-circuiting portion has a length equal to a ½ wavelength for a desired resonance frequency.