Generalized Efficiency and the Uncertainty of Millimeter Wave Power Standard

In the last decade, waveguide thermoelectric power sensors have been established as an alternative to thermistor mounts for millimeter wave power standards, and due to the detection principle and the nature of waveguides, the generalized efficiency is used as calibration quantity instead of the effective efficiency. In this paper, the generalized efficiency and the measurement uncertainty of waveguide thermoelectric sensors are presented and applied to calibrate other types of power sensors in a measurement set-up for frequency up to 170 GHz. Results for commercially available waveguide power sensors are discussed for the interfaces R 900 and R 1.4k.