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The Frequency Domain Thermoreflectance Technique for Thermal Property Measurements
Published on: December 5, 2025
Development of frequency modulation reflectometer for KSTAR tokamak: data analysis based on Gaussian derivative
1Diagnostics Research Team, National Fusion Research Institute, Daejeon 305-333, South Korea. shseo@nfri.re.kr
The Review of Scientific Instruments
|November 7, 2012
Summary
A new frequency modulation reflectometer measures KSTAR tokamak density profiles using Q and V bands. A novel phase detection algorithm enhances data analysis for improved plasma diagnostics.
Area of Science:
- Plasma physics
- Fusion energy research
- Diagnostic techniques
Background:
- Accurate plasma density profiling is crucial for understanding and controlling fusion devices like tokamaks.
- Existing reflectometry methods may require enhanced signal processing for complex plasma conditions.
Purpose of the Study:
- To develop and validate a frequency modulation reflectometer system for KSTAR tokamak.
- To introduce a new phase detection algorithm for analyzing amplitude and frequency modulated signals.
- To improve the precision of plasma density profile measurements.
Main Methods:
- Development of a dual-channel frequency modulation reflectometer operating in Q (33-50 GHz) and V (50-75 GHz) bands.
- Implementation of a 20 μs full band sweep with direct digitization at 100 MSamples/s.
- Creation and benchmarking of a novel phase detection algorithm for AM-FM signals.
Main Results:
- Successful development of a frequency modulation reflectometer for KSTAR.
- Demonstration of the new phase detection algorithm's effectiveness on synthesized AM-FM signals.
- Application of the algorithm to KSTAR reflectometer data analysis.
Conclusions:
- The developed frequency modulation reflectometer is suitable for KSTAR density profile measurements.
- The new phase detection algorithm provides a robust method for analyzing complex reflectometer signals.
- This advancement contributes to more accurate plasma diagnostics in fusion research.
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