Closely coupled directional antenna
US6025811A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 21, 1997 |
| Grant date | Feb 15, 2000 |
| Priority date | — |
| Expiry date | Apr 21, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01Q19/24
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
Disclosed is a dipole array antenna that is particularly useful at UHF and microwave frequencies. In an exemplary embodiment, the antenna is comprised of two dipole radiating elements--a driven dipole of length L1 and an unfed element closely spaced from the driven element, of length L2. The ratio L1/L2 is at least 1.1, and may be optimally set at about 1.3. Preferably, at a reference frequency in which VSWR is minimum, the length L2 of the unfed element is less than 0.45 wavelengths, and optimally, is in the range of 0.39-0.42 wavelengths, with dipole spacing in the range of 0.07 to 0.11 wavelengths at the reference frequency. Advantageously, the antenna exhibits a low VSWR in a 50 ohm system over an operating frequency band, whereby a matching network can be avoided. High gain and front-to-back ratio is also realizable while antenna size is kept small.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.