Wideband transmission-mode FET linearizer
US5191338A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 29, 1991 |
| Grant date | Mar 2, 1993 |
| Priority date | — |
| Expiry date | Nov 29, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2200/72
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A FET is operated without source-to-drain bias, with the source-to-drain conductive path coupled in series with a transmission line. A gate-to-ground impedance is selected in conjunction with a gate voltage near pinchoff to impress nonlinear distortion or gain and/or phase of signals traversing the source-to-drain conductive path. The nonlinear distortion can compensate for the amplitude distortion of a following amplifier, but the phase distortion may not be suitable for correcting that of the following amplifier. An inductor is bridged from source to drain, and corrects the phase without excessive effect on the amplitude. The magnitude of the inductor may be adjusted to minimize nonlinear amplitude change without affecting the phase change, whereupon the phase change may be made independent of amplitude change. A resistor in series with the bridging inductor can be selected to render amplitude change independent of phase change. Two such independent amplitude and phase correctors may be cascaded.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.