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Switched-Coupler Measurements for High Power FR Calibrations



J. W. Allen


Calibration of RF power sensors at levels greater than 10 mW and uncertainties on the order of 2 % need not require complex calorimetric methods. Using a series of cascaded directional couplers makes it possible to compare a high-power RF sensor against a calibrated, low-power, bolometer mount. For power levels up to 1 kW, typical uncertainties are on the order of 2 % or better. This paper describes the design and operational theory behind the new high-power measurement system recently developed at the National Institute of Standards and Technology (NIST). This new system makes use of the established low-power bolometer calibration service, and extends our measurement capability up to 1 kW in the 2 MHz to 1000 GHz frequency range.
Microwave Journal


microcalorimeter, microwave calorimeter, microwave power measurement, microwave power standard waveguide, microwave power standard


Allen, J. (2000), Switched-Coupler Measurements for High Power FR Calibrations, Microwave Journal (Accessed November 29, 2023)
Created February 29, 2000, Updated October 12, 2021