Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published May 2012 | public
Journal Article

Cryogenic Self-Calibrating Noise Parameter Measurement System


A system for measuring the noise parameters of a device at cryogenic temperatures is described. The method includes the thermal calibration of a module consisting of a noise diode, a dispersive coupling network, a temperature sensor, heater, and a bias-tee. The magnitude and phase of the reflection coefficient presented by the module vary rapidly with frequency and the noise output of the module can be thermally calibrated by changing the temperature of the module with an internal heater. The resulting variable impedance-calibrated noise source can be used to measure noise parameters of transistors or amplifiers over a frequency range of 0.4 to 12 GHz via the wideband frequency-variation method. The calibration scheme is not unique to the module and may be applied in general to any noise source. Calibration and noise parameter measurements are made at cryogenic temperatures on a discrete transistor and two different low-noise amplifiers. The results are compared against theoretical values and those obtained using independent measurements. To the best of the authors' knowledge, this is the first measurement of a transistor's noise parameters at cryogenic temperatures using such techniques.

Additional Information

© 2012 IEEE. Manuscript received October 24, 2011; revised February 03, 2012; accepted February 07, 2012. Date of publication April 03, 2012; date of current version April 27, 2012. This work was supported in part by the National Aeronautics and Space Administration under Grant NNX08A057G for the Stratospheric THz Observatory. The authors would like to thank Steve Smith of The California Institute of Technology, for the many helpful discussions regarding noise source design. The authors also wish to thank Hector Navarrete of the California Institute of Technology and Mary Wells of The Jet Propulsion Laboratory, for their help in the assembly of the module.

Additional details

August 22, 2023
October 17, 2023