Plasma and Fusion Research

Volume 17, 1205015 (2022)

Rapid Communications

Development of a Low Reflection Dummy Load for Calorimetric Power Measurements in High-Power Millimeter Wave Systems
Takayuki KOBAYASHI, Hibiki YAMAZAKI, Shinichi HIRANAI, Masayuki SAWAHATA, Masayuki TERAKADO, Kenji WADA, Fumiaki SATO, Jun HINATA, Ryosuke IKEDA, Takahiro SHINYA, Satoru YAJIMA, Ken KAJIWARA and Shinichi MORIYAMA
National Institutes for Quantum Science and Technology, Naka 311-0193, Japan
(Received 21 December 2021 / Accepted 30 January 2022 / Published 30 March 2022)


We developed a prototype low reflection dummy load for calorimetric power measurements in high-power millimeter wave systems. The dummy load is featured by low reflection of millimeter waves by an internal cylinder designed for increasing the length of the ray trajectory in the dummy load. This structure prevents the millimeter wave reflection from the dummy load by absorbing the waves by the inner surface of the cylinder. Initial tests at high powers of up to 0.5MW for 0.25 s were successfully able to measure output power with lower reflection back to the source than that of conventional short pulse dummy loads used in the past.


dummy load, high-power millimeter wave, reflection

DOI: 10.1585/pfr.17.1205015


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