PROBLEMS OF DESIGNING COOLED MIXERS FOR THE SUPERHIGH-FREQUENCY RANGE,
Abstract
The possibility of designing low-noise uhf mixers utilizing the low-temperature properties of semiconductors is discussed. A theoretical analysis was made of the relationship between the basic parameters of cooled mixers and the volt-ampere characteristics of diodes. The effect of low temperatures on both the parameters of mixer diodes and the mixers themselves was investigated experimentally on a stand capable of maintaining diode temperatures from room temperature (300K) to the temperature of liquid nitrogen (77K). On the basis of the results obtained, the following conclusions are made: (1) Cooled mixers based on semiconductor diodes can be used as successive stages in supersensitive receiving systems with quantum mechanical and cooled parametric amplifiers at the input. (2) The cooling of mixers utilizing D403V and D405V diodes reduces the noise factor to 0.6-3 db. (3) In designing cooled mixers with a nosie factor not worse than 5 db, diodes should be used with a transconductance increasing with a drop in temperature (e.g., germanium diodes) or with a high transconductance at very low temperatures (e.g., InSb diodes).
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 28, 1967
- Accession Number
- AD0660729
Entities
People
- V. D. Ekimov
- V. N. Alfeev
Organizations
- National Air and Space Intelligence Center