Frequency translation correction scheme for satellite communication system
US4901368A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Aug 2, 1989 |
| Grant date | Feb 13, 1990 |
| Priority date | — |
| Expiry date | Aug 2, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B7/208
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
In a time division multiple access satellite communications system having a master station and one or more remote stations, frequency offset through the translation oscillator in the satellite is corrected by transmitting a pilot frequency signal, reference to a high precision oscillator, through the satellite, so as to subject the pilot frequency signal to a frequency translation and monitoring the frequency translation of the pilot frequency signal as received at the master station subsequent to its transmission through the satellite. Signals to be transmitted over the satellite communications link from the master station to remote stations are subjected to a frequency translation that is effectively complementary to the monitored frequency translation. At a remote station, received signals are monitored for a difference in the corrected frequency (base upon the use of the precision oscillator at the master site) relative to a prescribed frequency and signals to be transmitted from the remote station to the master station are adjusted by an amount that effectively compensates for the difference between the prescribed frequency and the monitored frequency.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.