RF amplifier having switched load impedance for back-off power efficiency
US6522201B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 28, 2000 |
| Grant date | Feb 18, 2003 |
| Priority date | — |
| Expiry date | Sep 28, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03G1/0088
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
Efficiency of an RF/microwave power amplifier is increased at a back-off power level by increasing the load resistance of the amplifier at the reduced output power level as compared to load impedance at a higher power level including full operating power. The different load impedances can be realized with two amplification units in parallel each having different load impedances. Alternatively, a single amplification path can be provided with an output impedance matching network which is selectively bypassed for increased impedance load during back-off power operation. In another embodiment, the output impedance matching network can include a shunt inductance which is selectively switched into the network to increase impedance for back-off power operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.