Design and Testing of NFRad- :
Chriss A. Grosvenor · 2000
The NIST Noise Project has constructed and tested a new, automated, coaxial (GPC-7) radiometer for the measurement of noise sources in the 8 GHz to 12 GHz frequency band.It is an isolated, total-power radiometer that relies on lookup tables for relevant reflection coefficients and path asymmetry.Hence, much faster measurements at multiple frequencies result, compared to previous NIST systems.This technical note reviews the theory, describes the design of the system and its components, and details the testing procedures and the operation of the system.