Thermoelectric Sensors as Microcalorimeter Load

TL;DR

This paper discusses the use of thermoelectric power sensors as microcalorimeter load standards, offering advantages over bolometers, with high-frequency power standards achieved using coaxial thermocouples up to 34 GHz.

Contribution

It introduces thermoelectric sensors as transfer standards for high-frequency power measurement, replacing traditional bolometers, with demonstrated accuracy up to 1% from dc to 34 GHz.

Findings

Thermoelectric sensors are effective as microcalorimeter load standards.

High-frequency power standards achieved with coaxial thermocouples.

Accuracy ranges from 0.03% to 1% across the frequency spectrum.

Abstract

Thermoelectric power sensors can now be used as transfer standards, instead of bolometers, in the microcalorimeter technique. This alternative has the technical advantages to be less sensitive to absolute temperature and not downward frequency limited. At INRiM the high frequency power standards are now based on coaxial thermocouples from dc to 34 GHz. Modified commercial thermocouple mounts in 7 mm and 3.5 mm coaxial line are used to realize the national power standard with an accuracy ranging from 0.03 % to 1 % in the mentioned frequency range.