Frequency sharing for satellite communication system
US5822680A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 7, 1996 |
| Grant date | Oct 13, 1998 |
| Priority date | — |
| Expiry date | Nov 7, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B7/195
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A communication system and methods for sharing a common communication frequency, without interfering with a second communication system which has a plurality of satellites operating in geostationary orbits (GO) and ground stations (GS) which communicate with the satellites (GEO) on the common communication frequency, is disclosed. Conventional geostationary satellites broadcast in C and K.sub.u bands. Ground stations (GS) which receive these signals must have their antennas pointed toward the plane of the Equator (EQ). Satellites (10) which occupy inclined orbits (LO) and communicate with terrestrial terminals (12) propagate beams of energy that do not intersect the plane of the Earth's Equator. Terrestrial terminals (12) in the northern hemisphere communicate with a satellite (10) only when the sub-satellite point of the satellite (10) is at a latitude more northerly than the terrestrial terminal (12). Terrestrial terminals (12) in the southern hemisphere communicate with a satellite (10) only when the sub-satellite point of the satellite (10) is at a latitude more southerly than the terrestrial terminal (12). The spatial isolation of signals achieved by this novel pointing method…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.