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:
Jan. 07, 1992
Filed:
Jul. 03, 1990
George D Yarsunas, Vincentown, NJ (US);
Michael L Brennan, Howell, NJ (US);
James R Hendershot, Arroyo Grande, CA (US);
Radio Frequency Systems, Inc., Marlboro, NJ (US);
Abstract
A multi-band antenna is adapted to receive signals in the AM/FM bands and to receive and transmit signals in a significantly higher frequency band such as that used for cellular telephone. An AM/FM band antenna is formed of a tubular rod, and a higher frequency band antenna is formed using a centerfed coaxial dipole mounted on top of and coaxially with the AM/FM antenna. The dipole is fed by a coaxial rod attached to a coaxial cable extending through the AM/FM antenna. A cylindrical choke is disposed about the coaxial rod and is spaced a predetermined distance from the dipole antenna to reduce coupling between the AM/FM antenna and the high-frequency antenna. The choke functions to position the input impedance of the high-frequency antenna at the base of the choke in a manner so that a short matching transformer may be used at the base of the choke for connection to the coaxial cable. In matching the antenna in this manner at the base of the choke, the best possible VSWR characteristics of the antenna are preserved and the radiation pattern of the antenna's main lobe extends horizontally along a horizontal axis.