High efficiency RF power amplifier
US4717884A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 14, 1986 |
| Grant date | Jan 5, 1988 |
| Priority date | — |
| Expiry date | Apr 14, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2200/402
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A high efficiency RF power amplifier is disclosed in which a field effect transistor is operated in a class F mode. A third harmonic quarterwave open circuit transmission line stub having a Z.sub.O adjusted to provide capacitance series resonant with transistor inductance at the second harmonic is coupled to the transistor output lead to produce a low impedance at the channel drain of the transistor. Parallel resonance of the transistor die capacitance and interconnect inductance coupled to ground by the transmission line produces a third harmonic high impedance at the channel drain. Further lowpass output matching circuitry provides a constantly increasing impedance magnitude from the transistor die to the load and provides load mismatch isolation to the second and third harmonic impedances at the channel drain.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.