Development of electron cyclotron emission imaging system on Large Helical Device

Area of Science:

• Plasma physics
• Fusion energy research
• Diagnostic techniques

Background:

• The Large Helical Device (LHD) requires advanced diagnostics for plasma behavior analysis.
• Electron Cyclotron Emission (ECE) imaging and microwave imaging reflectometry are crucial for understanding plasma properties.

Purpose of the Study:

• To develop and implement a combined microwave imaging reflectometry and ECE imaging system for the LHD.
• To enhance the capability for spatially resolved measurements of plasma parameters.

Main Methods:

• Development of a wide-band two-dimensional horn-antenna mixer array (HMA).
• Integration of horn antennas, waveguides, mixers, and intermediate frequency circuits into the HMA.
• Utilizing a 95 GHz local oscillator and a 93 GHz high-pass filter for ECE signal selection.
• System frequency response spans 50 to 110 GHz.

Main Results:

• Successful development and integration of the combined imaging system.
• The HMA provides a wide frequency response suitable for LHD plasma diagnostics.
• Specific filtering enables selective detection of ECE signals.

Conclusions:

• The new combined system offers enhanced diagnostic capabilities for the LHD.
• This development advances the study of plasma dynamics in fusion devices.
• The system is expected to provide valuable data for fusion energy research.