Dual frequency vertical antenna
US5604506A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 13, 1994 |
| Grant date | Feb 18, 1997 |
| Priority date | — |
| Expiry date | Dec 13, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01Q5/40
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A dual frequency vertical antenna for radiating a first and a second airwave signal in response to a first and a second conducted signal, the first airwave signal having a first frequency and the second airwave signal having a second frequency lower than one-half the first frequency. The antenna includes a horizontal base member and a vertical mast, including a coaxially disposed rod, projecting upward from the base member to a masthead. For feeding the conducted signals, a lower mast extension projecting downward from the base member and a tuning sleeve projecting either upward or downward from the base member are tuned to 1/4 wavelength at the first frequency and a single coaxial cable is connected between the base member and a feedpoint on the rod. The first airwave signal radiates from a dipole formed of an 1/4 wavelength upper rod extension extending upward from the masthead and a concentric 1/4 wavelength upper sleeve external to the mast projecting downward from the masthead. The mast is 1/4 wavelength at the second frequency for radiating the second airwave signal from a dipole formed of the mast and the base member.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.