Title :
Analysis of the oscillation conditions in distributed amplifiers
Author_Institution :
Lab. d´´Electron. et de Phys. Appl., Limeil-Brevannes, France
fDate :
3/1/1989 12:00:00 AM
Abstract :
It has been shown that under certain conditions oscillation phenomena can occur in distributed amplifiers. It has also been demonstrated, using a simplified transistor model and a symmetrical amplifier with lumped circuit elements, that the oscillation depends directly on the transconductance gm of the active devices. The origin of this oscillation was found to be the loop formed in the distributed amplifier structure. The analysis has been experimentally verified in a practical 1-20-GHz monolithic MESFET amplifier. Finally, design guidelines have been established to avoid stability problems and to improve the capabilities of high-gain distributed amplifiers
Keywords :
MMIC; Schottky gate field effect transistors; circuit oscillations; field effect integrated circuits; microwave amplifiers; 1 to 20 GHz; distributed amplifiers; lumped circuit elements; monolithic MESFET amplifier; oscillation conditions; stability; symmetrical amplifier; transconductance; transistor model; Circuits; Coaxial components; Conductors; Distributed amplifiers; Eigenvalues and eigenfunctions; Impedance; Microwave theory and techniques; Transmission line theory; Transmission lines; Wire;
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on
