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The NIST Microwave Power Standards in Waveguide



J. W. Allen, Fred R. Clague, N T. Larsen, M. P. Weidman


The National Institute of Standards and Technology (NIST) microwave power standards in waveguide consist of automated microcalorimeters and associated transfer standards. Each transfer standard is a bolometric dc substitution power detector (a thermistor mount) of special design whose effective efficiency is measured by the microcalorimeter. The general design and operation of the microcalorimeter and transfer standard is described. The theoretical basis for the procedure used to determine the microcalorimeter correction factor, called the calorimetric equivalence, is also described. A detailed uncertainty analysis is included.
Technical Note (NIST TN) - 1511
Report Number


microcalorimeter, microwave, power, standard, waveguide


Allen, J. , Clague, F. , Larsen, N. and Weidman, M. (1999), The NIST Microwave Power Standards in Waveguide, Technical Note (NIST TN), National Institute of Standards and Technology, Gaithersburg, MD (Accessed April 19, 2024)
Created January 31, 1999, Updated October 12, 2021