Title :
A cryogenic 43-GHz-band low-noise amplifier for radio astronomy
Author :
Saito, Takashi ; Oohashi, Y. ; Kurihara, Hiroshi ; Hirachi, Yasutake ; Kasuga, Takeshi ; Miyazawa, K.
Author_Institution :
Fujitsu Lab. Ltd., Kawasaki, Japan
Abstract :
The authors describe the development of a cryogenic millimeter-wave-band HEMT (high electron mobility transistor) low-noise amplifier for radio astronomy application. The HEMT has a gate length of 0.25 mu m and a gate width of 100 mu m. To ensure stable operation, the amplifier was designed using S-parameters measured at a cryogenic temperature of 30 K. Very low noise temperature is obtained over a wide frequency range from 41.3 to 44.5 GHz by adopting a balanced amplifier configuration with a waveguide-type 3-dB hybrid. Minimum and maximum noise temperatures within the frequency range are 65 K and 95 K, respectively, at an ambient temperature of 30 K and amplifier gain of 11.5 dB.<>
Keywords :
S-parameters; cryogenics; high electron mobility transistors; microwave amplifiers; radioastronomy; solid-state microwave circuits; 0.25 micron; 11.5 dB; 30 K; 41.3 to 44.5 GHz; S-parameters; ambient temperature; balanced amplifier configuration; cryogenic millimeter-wave-band HEMT; low-noise amplifier; radio astronomy; waveguide-type 3-dB hybrid; Cryogenics; Frequency; HEMTs; Low-noise amplifiers; MODFETs; Millimeter wave measurements; Millimeter wave transistors; Operational amplifiers; Radio astronomy; Temperature distribution;
Conference_Titel :
Microwave Symposium Digest, 1989., IEEE MTT-S International
Conference_Location :
Long Beach, CA, USA
DOI :
10.1109/MWSYM.1989.38856
