Dual reflector antenna
US4356494A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 23, 1981 |
| Grant date | Oct 26, 1982 |
| Priority date | — |
| Expiry date | Jan 23, 2001 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01Q19/19
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
An earth station antenna is employed for telecommunicating with a satellite in combination with an automatic tracking apparatus. The antenna is a dual reflector antenna which comprises a main reflector, a sub-reflector and a primary radiator, and the used frequency band of the antenna is at least 1.8 octaves. A parameter t of the antenna, defined by a configuration of the primary radiator is less than 0.3 at the lowest operating frequency. The phase center of the primary radiator, at a low frequency within the operating frequency range, is made to correspond with the focus of the sub-reflector. The above parameter t is defined by: ##EQU1## where: .lambda.: wavelength in free space, PA1 D.sub.h : aperture diameter of the primary radiator, PA1 L.sub.h : center axial length from the radiator apex to the radiator aperture plane, and PA1 L.sub.s : length from the radiator aperture plane to the bottom surface of the sub-reflector.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.