RF/MW power standard realization without unitary efficiency assumption at dc/LF

TL;DR

This paper evaluates thermoelectric power sensors for RF/MW power standards, comparing calibration methods to enable primary standard realization without assuming unitary efficiency at low frequencies.

Contribution

It introduces a comparison of calibration methods for thermoelectric sensors to realize RF/MW power standards independently of unit efficiency assumptions.

Findings

Thermoelectric sensors show stable performance across RF and microwave frequencies.

Different calibration methods affect the effective efficiency of the sensors.

The approach enables primary power standard realization without relying on dc efficiency assumptions.

Abstract

Thermoelectric power sensors are widely used in commercial power meters at RF and microwaves, due to their superior robustness, stability, and accuracy if compared with other types of power sensors. Furthermore, their electrical architecture and related performance turned out to be very useful in the realization of the broadband primary power standards as alternative to resistive power sensors, i.e. bolometers. Hereby we present a comparison in term of effective efficiency of a thermoelectric sensor calibrated by applying two different methods of power substitution when used as thermal load in a coaxial microcalorimeter at RF and microwaves. The aim is to test a technology that could enable the realization of a primary RF/MW power standard independently of the assumption of unitary efficiency at the dc (or LF) reference power.