Improvements on INRIM Coaxial Microcalorimeter and Outcome of a Model Comparison

TL;DR

This paper reports hardware and software enhancements to the INRIM coaxial microcalorimeter, leading to improved stability, noise reduction, and measurement accuracy in primary power standard realization across 0.05-40 GHz.

Contribution

It introduces specific improvements in hardware and software for the INRIM microcalorimeter and compares the correction models to enhance measurement uncertainty.

Findings

Enhanced signal/noise ratio and drift reduction

Calibration of a 2.92 mm thermoelectric power sensor

Improved stability and repeatability of measurements

Abstract

This paper describes hardware and software improvements of the INRIM coaxial microcalorimeter together with their outcome on the primary power standard realization in the frequency band 0.05 - 40 GHz. A better temperature and power stabilization turned out to provide an improved signal/noise ratio and a drift reduction in every working condition of the microcalorimeter. The INRIM correction model is also compared to a traditional, but faster, one in terms of measurement uncertainty. Outcomes are presented in form of a 2.92 mm thermoelectric power sensor calibration together with results that show the improved stability and repeatability of the measurement system.