Dielectric rod polarizer having wedge shape polarizing portions
US4785266A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 6, 1987 |
| Grant date | Nov 15, 1988 |
| Priority date | — |
| Expiry date | Jul 6, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01Q19/08
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A microwave polarizer is provided in the form of a wedge at the termination of a rod of dielectric material. Preferably the wedge tapers exponentially in order to provide a good impedance match. Circularly polarized radiation propagating along the rod experiences a differential phase shift at the wedge. This phase shift may be arranged to be 90.degree., so that linearly polarized radiation exits from the wedge. A continuous circular or square guide is used to contain the dielectric rod so that simultaneous orthogonal signals can be converted to or from circular polarizations. Such a wedge termination may be provided at the end of a splashplate or polyrod antenna feed, for a satellite communication system, where right-handed circular polarization is used on the up-link and left-handed circular polarization is used on the down link. The conventional orthomode transducer may be dispensed with, thereby enabling the sub-reflector to be located closer to the main reflector, thus reducing blockage and increasing the bandwidth.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.