Accurate radio frequency filtering using active intermediate frequency feedback
US8798570B2 · kind B2 · utility
Inventors
Key dates
| Filing date | Dec 12, 2011 |
| Grant date | Aug 5, 2014 |
| Priority date | — |
| Expiry date | Apr 13, 2032 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B1/1027
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A receiver, such as a television tuner, includes a radio frequency (RF) filter circuit. The RF filter circuit includes a filter, a first node, and a second node coupled to the filter, and a conversion signal path having an input coupled to the first node and an output coupled to the second node, the conversion signal path having an active mixer coupled between the first node and the second node. The active mixer can include, for example, a first transconductor and a first mixer coupled in series between the first node and the second node. The RF filter circuit further includes a feedback signal path having an input coupled to the second node and an output coupled to the first node, the feedback signal path including a second transconductor and a second mixer coupled in series between the second node and the first node.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.