Transponder with selective antenna beam using shared antenna feed elements
US4956643A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 2, 1989 |
| Grant date | Sep 11, 1990 |
| Priority date | — |
| Expiry date | May 2, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B7/2041
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A transponder that selectively provides both global and spot beam antenna coverage. The transponder comprises a channel amplifier and an antenna feed network that includes coupler means for coupling energy into a plurality of power distribution networks that feed a plurality of antenna radiating elements that form a beam that illuminates the desired coverage area. A variable power divider is coupled to the amplifier that variably couples power along two channel output paths. Each output path includes a matched bandpass filter and the second output path includes a phase delay circuit. Selective control of the ratio of the power coupled to the respective output paths, and the phase delay provided by the phase delay circuit, provides for selective coupling of the total power provided by the channel amplifier to either the full set, or a selected subset of the antenna elements which generates global and spot beams, respectively. A more complex version is described which additionally incorporates an N-channel multiplexer. The present invention may also be employed as an interface circuit that may be interposed between a transponder channel amplifier and an antenna feed network to retrof…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.