Abstract-Terahertz power calibration using absolute reference calorimeter

Hitoshi Iida, Moto Kinoshita, Kuniaki Amemiya, Yuya Tojima

https://onlinelibrary.wiley.com/doi/abs/10.1002/tee.22929?af=R

Here, we demonstrate an accurate terahertz (THz) power calibration toward tens of nanowatt levels at room temperature. A power reference standard based on a calorimeter with extremely low noise is realized by introducing vacuum insulation panels utilized for thermal insulation. The standard provides a measurement capability of 26.7 nW with the expanded uncertainty of 4.2% (k = 2) at 1 THz. The direct‐comparison calibration of a commercially available power meter is performed by considering its detectable power levels using the standard. A thermopile‐type power meter is used as the device under test, and its calibration factors are determined at 1 and 1.5 THz over a power‐level range of 0.66–1.56 µW. We evaluate the measurement uncertainties of the calibration and find a relative expanded uncertainty of 4.8–9.0% (k = 2).

 © 2019 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.

Abstract-Calibration of a Terahertz Attenuator by a DC Power Substitution Method

Hitoshi Iida, Moto Kinoshita, Kuniaki Amenity

http://ieeexplore.ieee.org/document/7802555/

An attenuation calibration system is developed using an isothermal temperature control-type calorimeter for a terahertz (THz) attenuator. This system is based on a power ratio measurement by dc power substitution. A highly sensitive calorimeter achieves a simple and accurate attenuation calibration at room temperature. Calibration is performed for metalized-film attenuators at 1 THz using a photomixer as the THz source. The measurement uncertainties in the system are evaluated, and the expanded uncertainty is found to be 0.19–0.84 dB ( k=2 ) for an attenuation measurement range up to 12 dB.