Development of WR-5 Waveguide Calorimeter for Millimeter Wave Power Standard

This paper reports a rectangular waveguide calorimeter for a WR-5 frequency band (140 GHz to 220 GHz). An SI traceable measurement of the absolute millimeter wave power with the calorimeter can be realized by DC substitution and correction with adiabatic efficiency, the DC substitution coefficient, transmission loss, scattering parameter, etc. As a result, we demonstrated that the developed calorimeter measured a millimeter wave power at a level of 0.5 mW, at a frequency range from 140 GHz to 220 GHz.