Direct conversion receiving apparatus and celluar phone
US7454186B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 29, 2005 |
| Grant date | Nov 18, 2008 |
| Priority date | — |
| Expiry date | Feb 14, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B1/30
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
The direct conversion receiving apparatus has a gain control amplifier for variably amplifying a base band signal based on a gain switching control signal. A high pass filter has a first circuit including capacitors connected in parallel that are inserted in a path connecting an input terminal to an output terminal and switching effective total capacitance of the capacitors based on a first time constant switching control signal, and a second circuit including a resistor for providing a predetermined direct current voltage to the output terminal and switching the effective resistance value of the resistor based on a second time constant switching control signal. A control circuit outputs the gain switching control signal, and the first and second time constant switching control signals according to the change of the gain control of said gain control amplifier.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.