Tunable RF filter
US9246453B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 15, 2008 |
| Grant date | Jan 26, 2016 |
| Priority date | — |
| Expiry date | Mar 11, 2032 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2203/5039
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A tunable RF filter, comprising: an emitter follower stage (2); and a common emitter stage (4); the common emitter stage (4) providing feedback to the emitter follower stage (2). The common emitter stage (4) may comprise a first transistor (Ti) being the only transistor of the common emitter stage (4); and the emitter follower stage (2) may comprise a second transistor (T2) being the only transistor of the emitter follower stage (2). A further tunable RF filter provides improved linearity, comprising: an emitter follower stage (22); a joint common emitter and emitter follower stage (24); and a gain stage (26); a common emitter output of the joint common emitter and emitter follower stage (24) providing feedback to the emitter follower stage (22), and an emitter follower output of the joint common emitter and emitter follower stage (24) providing an input to the gain stage (26).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.