In-phase and quadrature-phase signal amplitude and phase calibration
US7894547B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 28, 2009 |
| Grant date | Feb 22, 2011 |
| Priority date | — |
| Expiry date | Jul 28, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2027/0038
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
In-phase (I) and quadrature-phase (Q) signals are corrected for both amplitude and phase imbalances by passing the I and Q signals successively through a first amplitude correction stage, a sum-difference stage, and a second amplitude correction stage. The first amplitude correction stage balances the signal levels of the I and Q signals. The sum-difference stage produce a sum of the input I and Q signals, and a difference of the input I and Q signals, resulting in ideal quadrature in the outputs produced. The second amplitude correction stage corrects the amplitude differences from the sum-difference stage. Circuit configurations are used that minimize errors produced by the signal processing stages.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.