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. 10, 1989
Filed:
Jan. 07, 1988
William Tan, Lantana, FL (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
The antenna system of the present invention includes a single loop antenna connected in series with a ferrite core loop antenna. The single loop antenna is enclosed in a nonconductive housing, such as a band, which surrounds the wrist. The single loop antenna has a first end grounded and is connected in series with a first variable capacitive element for adjusting the resonant frequency of the single loop antenna. The ferrite core loop antenna is connected to a second variable capacitive element for adjusting the resonant frequency of the ferrite core loop antenna. One end of the ferrite core loop antenna is applied as an input to a communication receiver such as a paging receiver. The outstanding feature of the antenna system is that the axis of the single loop antenna is perpendicular to and noncoplanar with the ferrite core loop axis for enhancing the sensitivity and minimizing body effects caused by hand movements.