Circuit configuration for filtering a radio-frequency signal
US6795696B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Feb 20, 2001 |
| Grant date | Sep 21, 2004 |
| Priority date | — |
| Expiry date | Jun 17, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03J3/08
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A circuit configuration for filtering a radio-frequency signal, in particular, in tuners for television sets, includes a control signal connection for feeding in a control signal, a controllable-frequency oscillator, at least one filter having an adjustable passband for a useful signal, and a device for providing a correction signal. The filters are, preferably, tracking filters whose filter band can be shifted by a control signal. At least one filter has a variable-frequency element with a first connection and a second connection. The first connection is coupled to the control signal connection, and the correction signal device is coupled to the second connection. For fine tuning production tolerances, the filters are supplied with a correction signal, which is applied to the other pole of the variable-frequency element of the filter as compared with the control signal. The value range of the correction signals is limited to the correction range and is much lower than the value range for the control signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.