System and method for correction of I/Q angular error in a satellite receiver
US5812927A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 10, 1997 |
| Grant date | Sep 22, 1998 |
| Priority date | — |
| Expiry date | Feb 10, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04H40/90
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A DBS receiver front end which converts the received signal directly to the baseband representation and maintains a high performance with a new techniques for tracking and counteracting frequency drift, and correcting I/Q angular error and amplitude imbalance. The DBS receiver front end comprises a tuner and a demodulator/decoder. The tuner receives a high frequency signal and converts it to a baseband signal having a frequency offset error. In one embodiment, the DBS receiver front end includes a demodulator/decoder which digitally performs I/Q angular error correction. The tuner converts the high frequency signal to a baseband signal having an in-phase and a quadrature-phase component. Ideally, the components are separated by ninety degrees, but typically an angular error exists. The demodulator/decoder includes an adaptive equalizer for correcting the angular error. Having the equalizer allows for relaxed tolerances in the tuner.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.