Accession Number : AD0660729

Title :   PROBLEMS OF DESIGNING COOLED MIXERS FOR THE SUPERHIGH-FREQUENCY RANGE,

Corporate Author : FOREIGN TECHNOLOGY DIV WRIGHT-PATTERSON AFB OHIO

Personal Author(s) : Alfeev,V. N. ; Ekimov,V. D.

Report Date : 28 APR 1967

Pagination or Media Count : 26

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).

Descriptors :   (*CRYSTAL MIXERS, ULTRAHIGH FREQUENCY), COOLING, NOISE(RADIO), SEMICONDUCTOR DIODES, LOW TEMPERATURE, CRYOGENICS, MIXERS(ELECTRONICS), USSR

Subject Categories : Electrical and Electronic Equipment

Distribution Statement : APPROVED FOR PUBLIC RELEASE