FM stereo decoder incorporating Costas loop pilot to stereo component phase correction
US7787630B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 16, 2006 |
| Grant date | Aug 31, 2010 |
| Priority date | — |
| Expiry date | Jul 1, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04H40/54
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A novel system and method for correcting the residual phase offset between a recovered pilot signal and the received stereo signal. The invention uses a Costas loop as an auxiliary loop in addition to the pilot recovery phase locked loop (PLL) to lock onto the stereo component itself. This auxiliary loop functions to generate a pilot to stereo component phase correction signal that is added to the stereo carrier phase The resultant phase is used to generate the recovered pilot carrier used to demodulate the stereo MPX signal. The Costas loop is activated together with the main pilot recovery PLL that locks onto the pilot tone in the demodulated MPX signal. The auxiliary Costas loop is operative to track and determine a residual phase error of up to several degrees.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.