Method for receiving signals from a constellation of satellites in close geosynchronous orbit
US6075969A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 9, 1997 |
| Grant date | Jun 13, 2000 |
| Priority date | — |
| Expiry date | Jan 9, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02D30/70
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A C-Band or Ku-Band satellite communication system uses a relatively small receiving antenna while operating within current FCC designated bandwidth and using existing satellite configurations. Aperture synthesis techniques create nulls in orbit locations from which potential interference is expected. Bandwidth inefficient modulation techniques reduce transmission power flux density. Video compression reduces the power necessary to transmit video information. These three features make possible a receiving antenna with a receiving area equivalent to that of a three foot diameter dish, at C-Band frequencies. Comparable reductions are possible for Ku-, Ka-, S- and L-Band systems. Compressing the data reduces the required transmitted power by a factor of ten. Spreading the bandwidth reduces the power density below the FCC limitation. However, reducing the antenna diameter increases the beam width of the antenna, hence, the smaller antenna can no longer discriminate between adjacent C-Band satellites in their current orbital configuration. By designing the receiving antenna with nulls in orbital locations where potentially interfering satellites would be located, the small antenna avoid…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.