Multichannel correlation receiver for determining depolarization of signals along signal propagation paths
US4293945A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 29, 1979 |
| Grant date | Oct 6, 1981 |
| Priority date | — |
| Expiry date | Aug 29, 1999 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B7/002
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A multichannel correlation receiver at an earth station is provided for determining the depolarization effects of atmospheric conditions on satellite communications. The receiver provides a first co-polarized signal and a second, relatively weak, cross-polarized signal indicative of the depolarization effects, and uses a phase locked loop demodulator to produce a noise free replica of the relatively strong co-polarized signal. This co-polarized signal is highly correlated with the second cross-polarized signal and is mixed therewith to provide a relatively noise free, narrow band signal which has a level indicative of the cross-polarization signal strength for both up-link and down-link propagation paths. The relative signal strengths are recorded on a digital storage means and provide an accurate measure of the depolarization effects of the existing atmospheric conditions. A programmable local oscillator also provides multiple channel capability.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.