Carrier recovery system for a vestigial sideband signal
US5894334A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 5, 1996 |
| Grant date | Apr 13, 1999 |
| Priority date | — |
| Expiry date | Sep 5, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N21/426
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A television signal receiver for processing an HDTV signal transmitted in a vestigial sideband (VSB) format includes input complex filters shared by a timing recovery network (30) and a carrier recovery network (50). The filter network includes a pair of upper and lower band edge filters (20, 22) mirror imaged around the upper and lower band edges of the VSB signal for producing suppressed subcarrier AM output signals. The timing recovery network includes a phase detector (28, 38, 62) and responds to an AM signal derived from the two filters (via 26) for synchronizing a system clock (CLK). The carrier recovery network (50) also includes a phase detector (54, 60, 62, 64), and responds to outputs from one or both of the filters for producing an output error signal (.DELTA.) representing a phase/frequency offset of the VSB signal. The error signal is used to reduce or eliminate the offset to produce a recovered baseband or near baseband signal. A subsequent equalizer eliminates any residual phase offsets in the recovered signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.