Direct data tuner
US5742357A · kind A · utility
13Cited by
6References
12Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Apr 12, 1996 |
| Grant date | Apr 21, 1998 |
| Priority date | — |
| Expiry date | Apr 12, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N21/42607
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An improved tuner for recovery of data having a data bandwidth embedded in a video signal transmitted in association with a video carrier frequency is disclosed. The entire video signal is shifted to the intermediate frequency bandwidth, thereby shifting the data bandwidth to an IF data bandwidth. The IF data bandwidth is then filtered to block as much of the spectrum of the IF signal that is outside of the IF data bandwidth. The filtered IF data bandwidth is then demodulated again using an IF carrier generated by a local oscillator that tracks frequency drift in the carrier.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.