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:
Sep. 18, 2001
Filed:
Feb. 23, 1999
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
An antenna device includes radiation elements formed on a common antenna board, a feeding unit for feeding the radiation elements, and a ground plate provided in electrically-spaced relation to the radiation elements. The ground plate is mounted on a box-like metal body to form a short-circuit therewith. The radiation elements may have different line lengths for transmitting and receiving a plurality of wavelengths. The feeding unit may include a first radiation element having a different electrical length than a second radiation element, a first feed point for feeding electric power to the first radiation element, and a second feed point for feeding radiation elements are grounded to the ground plate at respective first and second ground points. The difference from the first and second feed points to their respective ground points are different from one another. The antenna device may have a value equal to (H)÷(&Lgr;), where (H) is the distance between the radiation elements and the ground plate, and (&Lgr;) is a wavelength of at least one frequency transmitted or received by the antenna device, and the distance H satisfies a relationship of 1÷250≦(H)÷(&Lgr;)≦1÷100.