Title :
Phase noise in cryogenic microwave HEMT and MESFET oscillators
Author :
Llopis, Olivier ; Plana, Robert ; Amine, Hicham ; Escotte, Laurent ; Graffeuil, Jacques
Author_Institution :
LAAS-CNRS, Toulouse, France
fDate :
3/1/1993 12:00:00 AM
Abstract :
The influence of cooling on the phase noise of HEMT and MESFET oscillators is addressed. The initial measurements of the device DC characteristics and low-frequency noise (0.1 kHZ-100 kHz) under cooling give indications on the suitability of a given device for use in low-phase-noise cooled oscillators. Cooled pseudomorphic AlGaAs-GaInAs-GaAs HEMTs (PHEMTs) turn out to be particularly well-suited as they are free of collapse and they are free of g-r noise in the frequency range of interest. The authors report on 4 GHz oscillators operated at 110 K and featuring a phase noise below -100 dBc/Hz at 10 kHz from the carrier in spite of a very modest loaded Q (160). It is suggested that high-temperature-superconductor resonators could greatly enhance the spectral purity of PHEMT oscillators
Keywords :
Schottky gate field effect transistors; cooling; cryogenics; high electron mobility transistors; microwave oscillators; semiconductor device noise; solid-state microwave circuits; 0.1 to 100 kHz; 110 K; 4 GHz; AlGaAs-GaInAs-GaAs; MESFET oscillators; PHEMT oscillators; SHF; cooling; cryogenic operation; device DC characteristics; high-temperature-superconductor resonators; low-frequency noise; low-phase-noise cooled oscillators; phase noise; pseudomorphic HEMT; Cooling; Cryogenics; HEMTs; Low-frequency noise; MESFETs; Microwave devices; Microwave oscillators; Noise measurement; PHEMTs; Phase noise;
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on
