On-signal quadrature modulator calibration
US6931343B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 19, 2003 |
| Grant date | Aug 16, 2005 |
| Priority date | — |
| Expiry date | Nov 28, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B17/14
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An on-signal calibration system I and Q signals of a transmitter to remove distortions in the RF output signal. The transmitter generates I and Q values and converts, modulates and combines the I and Q values into the RF output signal for transmission. The calibration system includes a detector, a sampler, a selector, an imbalance estimator, and an IQ corrector. The detector senses the RF output signal and provides a detection signal indicative thereof. The sampler samples the detection signal and provides digital samples. The selector selects from among the digital samples that correspond to predetermined ranges of the I and Q values, or otherwise predetermined selection boxes at predetermined phases. The imbalance estimator determines at least one imbalance estimate based on selected digital samples. The IQ corrector corrects the I and Q values using at least one imbalance estimate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.