Transmitter and method with RF power amplifier having predistorted bias
US9093960B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jul 24, 2013 |
| Grant date | Jul 28, 2015 |
| Priority date | — |
| Expiry date | Nov 20, 2033 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2200/432
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A transmitter (32) generates a time-varying stabilized bias signal (82) from which sub-RF distortion signals (26, 29) have been cancelled. The distortion signals (26, 29) are byproducts of imperfect amplification and of biasing networks. An envelope amplifier (84) includes a high bandwidth differential input, linear, bias signal amplifier (120) and a low bandwidth switching amplifier (122) coupled together to achieve both a high bandwidth and high efficiency. A control loop (154) feeds a portion of the voltage V(t) from a conduction node (146) of the RF power amplifier (36) to one of the differential inputs of the linear bias signal amplifier (120), while a bias control signal (92) drives the other differential input. The portion of voltage V(t) fed to bias signal amplifier (120) is a low power portion from which the RF portion has been removed. A bias signal (128) may be predistorted to cancel distortion signals (26, 29).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.