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:
Feb. 20, 1979
Filed:
Aug. 19, 1977
Carlyle J Sletten, Acton, MA (US);
Abstract
A portable multiband H.F. antenna that has minimum ground area requirements and that is capable of transmitting electromagnetic wave radiation with horizontal polarization, azimuth plane omnidirectional patterns and a null in the vertical beam pattern is realized by means of an easily erectable tower type radiator. The tower structure has adjacent conductive leg members that define an elongated antenna slot aperture the total length of which is resonant to the lowest operating frequency band. A microwave transmission line resides along one side of the slot and the slot aperture is fed by shorting the transmission line to the oposite side of the slot. Operation at higher frequency bands is achieved by shorting out sections of the slot aperture on both sides of the feed. An array of radiating slot apertures can be provided by shorting the full slot aperture into sections and feeding each slot section separately. The addition of capacitance to the feed circuit permits operation at frequency bands below that provided for by the full slot aperture length.