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Design and Testing of NFRad - A New Noise Measurement System



Chriss A. Grosvenor, James P. Randa, Robert L. Billinger


The NIST Noise project has constructed and tested a new, automated, coaxial (GPC-7) radiometer for the measurement of noise sources in the 8-12 GHz frequency band. It is an isolated, total-power radiometer that relies on lookup tables for relevant reflection coefficients and path asymmetry. This permits measurements at multiple frequencies much more quickly than on previous NIST systems. This paper reviews the theory, describes the design of the system and its components, and details the testing procedures and the operation of the system.
Technical Note (NIST TN) - 1518
Report Number


noise, noise figure, noise measurement, noise temperature, radiometer, thermal noise


Grosvenor, C. , Randa, J. and Billinger, R. (2000), Design and Testing of NFRad - A New Noise Measurement System, Technical Note (NIST TN), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed April 22, 2024)
Created March 1, 2000, Updated February 19, 2017