Comparison Among Coaxial Microcalorimeter Models

Thermoelectric power sensors used as power transfer standards are promising devices for further enhancements of the microcalorimetric technique in the high-frequency field. A coaxial microcalorimeter has been studied, based on thermoelectric power sensors, at the Istituto Nazionale di Ricerca Metrologica (INRIM). In the literature, several models have been proposed, considering different calibration processes and error sources. Hereby, we analyze these models in terms of the total uncertainty for the 3.5-mm coaxial line case between 10 MHz and 26.5 GHz. The advantages and disadvantages of the models are highlighted.