Method and apparatus for DC offset removal in a radio frequency communication channel
US6975848B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 8, 2002 |
| Grant date | Dec 13, 2005 |
| Priority date | — |
| Expiry date | Mar 13, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B1/30
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A filter module for reducing a DC offset voltage in a radio frequency communication channel is described. A first capacitor is coupled between a first differential input node and a first differential output node. A second capacitor is coupled between a second differential input node and a second differential output node. An active variable resistor is coupled between the first differential output node and the second differential output node. The active variable resistor receives a control signal. The control signal adjusts the value of the active variable resistor, which adjusts the frequency response of the filter module. The rate at which the filter module reduces DC offset voltages is thereby adjusted. The filter module is also adaptable to single-ended applications.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.