Highly linear and very low-noise down-conversion mixer for extracting weak signals in the presence of very strong unwanted signals
US7840197B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 2, 2007 |
| Grant date | Nov 23, 2010 |
| Priority date | — |
| Expiry date | Jun 4, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03D7/165
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A highly linear and very low-noise down-conversion mixer for extracting weak signals in the presence of very strong unwanted signals is disclosed. Aspects of an embodiment may include a source follower circuit in a transmitter front end of a mobile terminal. The source follower circuit may receive RF signals prior to the RF signals being amplified by a power amplifier for transmission. The RF signals may comprise in-phase and quadrature components. The source follower circuit may generate output RF voltage signals, and communicate the output RF voltage signals to a switching circuit via a coupling capacitor. The switching circuit may down-convert the communicated output RF voltage signals to generate differential baseband signals. The capacitance of the coupling capacitor may be changed to change gain and/or linearity of the differential baseband signals. Each of the differential baseband signals may be low-pass filtered to attenuate higher frequencies.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.