Mr. Kornpatsitt Promasa, from NIMT, visited the Korea Research Institute of Standards and Science (KRISS), Republic of Korea, to conduct research on “Noise Figure Measurement” from 10–17 March 2026.
The primary objective of this visit was to collaborate with KRISS experts and enhance technical knowledge in noise measurement, RF systems, and advanced metrology techniques. During the research stay, Mr. Kornpatsitt engaged in discussions and experimental work with leading researchers, including Dr. Dong-Joon Lee, Dr. Tae Weon Kang, and Dr. Jae-Youg Kwon.
A key focus of the research was the development and application of electro-fiber optic probes for measuring electric and electromagnetic fields. Two types of probes were studied: the round-trip probe and the fabricated electro-optic (EO) sensor. These sensors are designed for high durability, capable of withstanding electric fields up to approximately 10 kW, and can operate over a wide frequency range. Their applications include measurements in TEM cells, near-to-far-field projections of horn antennas, and advanced antenna characterization systems.
In addition, Mr. Kornpatsitt studied the calibration and measurement of noise figure (NF), an essential parameter used to evaluate the performance of RF and electronic devices. The work involved the Y-factor method using calibrated noise sources to determine the Excess Noise Ratio (ENR) and noise temperature. Practical measurements were carried out on low noise amplifiers (LNAs), where both gain and noise figure were evaluated using KRISS standard systems.
The visit also provided exposure to advanced RF metrology infrastructure at KRISS, including:
– Microcalorimeter systems serving as primary standards for RF power measurements (10 MHz to 50 GHz),
– Comparison-based calibration systems for power sensors,
– D-band waveguide impedance standards for high-frequency applications (110–170 GHz),
– Robotic measurement systems for next-generation communication technologies, including millimeter-wave and sub-terahertz measurements.
Furthermore, innovative applications such as 5G antenna measurements (Sub-6 GHz), near-field imaging systems, and studies on human body blockage effects at sub-terahertz frequencies were explored.
This research visit significantly enhanced knowledge and technical capabilities in fiber optic sensing, noise measurement, RF power calibration, and advanced antenna measurement techniques. As a follow-up, NIMT plans to implement hybrid comparison methods for two-port amplifier measurements, focusing on gain and noise figure.
The collaboration between NIMT and KRISS continues to strengthen international cooperation in metrology and supports the advancement of measurement science for emerging communication technologies.
