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Precision Measurement Method for Cryogenic Amplifier Noise Temperatures Below 5 K

Published

Author(s)

James P. Randa, Eyal Gerecht, Dazhen Gu, Robert L. Billinger

Abstract

We report precision measurements of the effective input noise temperature of a cryogenic (liquid helium temperature) MMIC amplifier at the amplifier reference planes within the cryostat. A method is given for characterizing and removing the effect of the transmission lines between the amplifier reference planes and the input and output connectors of the cryostat. In conjunction with careful noise measurements,this method enables us to measure amplifier noise temperatures below 5 K with an uncertainty of 0.3+- K. The particular amplifier that was measured exhibits a noise temperature below 5.5K from 1 to 11 GHz, attaining a minimum value of 2.3K+- 0.3K at 7 GHz. The measured amplifier gain is between 33.4dB+- 0.3 dB and 35.8 dB +- 0.3 dB over the 1-12 GHz range.
Citation
IEEE Transactions on Microwave Theory and Techniques
Volume
54
Issue
3

Keywords

amplifier noise, cryogenic MMIC amplifier, noise temperature, noise measurement, thermal noise

Citation

Randa, J. , Gerecht, E. , Gu, D. and Billinger, R. (2006), Precision Measurement Method for Cryogenic Amplifier Noise Temperatures Below 5 K, IEEE Transactions on Microwave Theory and Techniques, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=32017 (Accessed April 17, 2024)
Created February 28, 2006, Updated October 12, 2021