Structures and methods for direct conversion from radio frequency modulated signals to baseband signals
US6711397B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 20, 2000 |
| Grant date | Mar 23, 2004 |
| Priority date | — |
| Expiry date | Jul 12, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03D2200/0047
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A direct conversion receiver is disclosed that converts RF signal into corresponding quadrature baseband signals without requiring conversion through an intermediate frequency. The direct conversion receiver abates local oscillator leakage, increases dynamic range and increases RF selectivity as compared to conventional direct conversion circuits. The circuit includes an in-phase branch and a quadrature-phase branch, each branch including two mixers instead of the conventional one. Each mixer is provided with balanced control signals that include a primary control signal and a complementary control signal. For each branch, the signals from the mixer pass through an operational amplifier and a low pass filter to extract the corresponding baseband signal component.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.