Television receiver for digital signals with offset tuning provisions
US7239358B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Jul 13, 2000 |
| Grant date | Jul 3, 2007 |
| Priority date | — |
| Expiry date | Jun 30, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N21/4382
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A television receiver for receiving digital and analog signals that reduces adjacent channel interference when receiving digital signals susceptible to interference caused by a lower adjacent NTSC signal. Upon receiving the digital signal, the receiver heterodynes the digital signal with a local oscillator (LO) signal to produce an intermediate frequency (IF) signal. A microprocessor searches a memory unit for stored information regarding the digital broadcast channel and determines the presence or absence of a lower adjacent NTSC channel. In the case a lower adjacent NTSC channel is present, the microprocessor shifts the frequency of the LO signal causing the IF signal to shift towards the lower band edge of a surface acoustic wave (SAW) filter present in a digital signal processor further attenuating the lower adjacent NTSC channel.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.