Apparatus and method for generating accurate quadrature over a frequency range
US6222405A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 22, 2000 |
| Grant date | Apr 24, 2001 |
| Priority date | — |
| Expiry date | Feb 22, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H11/16
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
The invention produces an accurate quadrature relationship for a range of frequencies using passive components in the primary quadrature splitting circuits. A reference oscillator (202) generates a reference signal which is fed to a conventional passive quadrature splitter circuit (204). However, since the reference circuit provides signals over a range of frequencies, the output signals of the passive quadrature splitter may not have an accurate quadrature relationship. The output signals of the passive quadrature splitter are then equalized in magnitude, and the sum and difference of the signals are produced, which will be in an accurate quadrature relationship.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.