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:
Dec. 02, 1986
Filed:
Aug. 08, 1984
John Ma, Milpitas, CA (US);
Other;
Abstract
An elongated active element for an antenna has an internal resonator providing a high quality matching impedance. The internal resonator is formed by a pair of conductors including an outer conductor and a coaxial inner conductor that is connected to signal ground. The signal connection of the active element is made to one end of the outer conductor in the neighborhood of the ground connection to the inner conductor. The inner conductor is shorted to the outer conductor at approximately a quarter of a wavelength, plus an integral number of half wavelengths, from the signal and ground connections to provide a parallel-resonant condition complementing the series resonant characteristics of the radiation impedance of the active element. Preferably, the active element is approximately a quarter wavelength long, and may be lengthened or shortened to obtain a desired radiation resistance. The antenna is easily fabricated from a length of coaxial cable. The antenna is advantageously used in pagers and other kinds of VHF and UHF radios, since the coaxial cable can be coiled to fit inside a miniature radio housing. For relatively low frequencies, a coil of coaxial cable including a number of turns provides a relatively efficient broadband antenna.