Collapsible, low visibility, broadband tapered helix monopole antenna
US5216436A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 31, 1991 |
| Grant date | Jun 1, 1993 |
| Priority date | — |
| Expiry date | May 31, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01Q1/362
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A collapsible `bedspring` monopole antenna is configured to be effectively non-observable in its collapsed condition and, when deployed, remains sufficiently compact to ensure very low observability characteristics, while providing broadband coverage over a wide viewing aperture. The antenna is comprised of a conductor formed as a tapered helix. One end of the conductor is coupled to an antenna feed. The outer end of the helix is looped around on itself to form a circular loop. A plurality of substantially rectilinear `radials` are soldered to distributed locations around its circular loop, so as to extend outwardly and tangentially from the outer perimeter of the loop and provide `top hat` capacitive matching elements. To define the height of the deployed antenna and to electrically short out plural locations of the helix, a plurality of conductive straps are joined to respective spaced apart locations of the helix. When allowed to expand toward its deployed configuration, the bedspring imparts a tensile force to the straps, which are pulled taught, thereby limiting the expansion of the bedspring. That portion of the helix between the closest point of strap attachment and its feed…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.