The paper shows the determination and application of the generalized efficiency of waveguide thermoelectric power sensor and the uncertainty in the direct transfer system to establish measurement traceability of the millimeter wave power to the primary standard. The waveguide thermoelectric sensor with its generalized efficiency can be used as a transfer standard to calibrate all types of power sensors to determine both the generalized efficiency and the calibration factor.

In measurement applications many devices with two ports have different interfaces at their two ports and are commonly referred to as adapters. The interface e.g. can be a coaxial connector, a rectangular waveguide flange, or a coplanar waveguide probe tip. Two suitable methods for the measurement of such adapters are compared. The first one is a VNA measurement method using only one port calibration standards and one port measurements. It will be compared to a two port calibration method.