Method and apparatus for down-conversion of radio frequency (RF) signals with reduced local oscillator leakage
US6973297B1 · kind B1 · utility
8Cited by
58References
24Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Sep 1, 2000 |
| Grant date | Dec 6, 2005 |
| Priority date | — |
| Expiry date | Apr 25, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B2001/0491
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
This patent describes a method of removing the LO-leakage and 1/f noise problems associated with direct conversion RF receivers and other demodulators. In order to solve this problem a virtual LO™ signal is generated within the RF signal path which is tuned to the incoming RF signal. The virtual local oscillator (VLO) signal is constructed using signals that do not contain a significant amount of power (or no power at all) at the LO frequency. Any errors in generating the virtual LO signal are minimized using a closed loop correction scheme.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.