Carrier-blanking mechanism for sweeping detector used to measure and correct RF power amplifier distortion
US6407635B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 10, 2001 |
| Grant date | Jun 18, 2002 |
| Priority date | — |
| Expiry date | Aug 10, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F1/3247
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
RF power amplifier distortion can be accurately measured in the presence of multi-frequency input signals, by using a swept local oscillator to tune RF input and output receivers. The power detected by the input receiver is compared with a threshold associated with the carrier. Whenever the power detected by the input receiver exceeds the threshold—indicating that the input receiver is tuned on carrier energy—the signal path through the output receiver is blanked. The sweeping action combined with selective blanking of the output receiver creates an adaptive notch filter, which allows for the direct measurement of low level distortion power in the presence of high power carriers. This distortion power is digitized and can be processed to control pre-distortion correction circuitry or gain/phase adjustment circuitry of a feed-forward error correction loop.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.