Development of microwave imaging reflectometry in large helical device.

Area of Science:

• Physics
• Engineering
• Plasma Science

Background:

• Microwave Imaging Reflectometry (MIR) is crucial for plasma diagnostics.
• Existing MIR systems often rely on expensive waveguide technology.
• Large Helical Device (LHD) research requires advanced diagnostic tools.

Purpose of the Study:

• To develop key devices for a new Microwave Imaging Reflectometry (MIR) system for the Large Helical Device (LHD).
• To reduce the cost of MIR systems by utilizing commercial wireless components.
• To enable 2-D and 3-D microwave imaging for plasma diagnostics and industrial applications.

Main Methods:

• Development of a 2-D mixer array using stacked 1-D planar Yagi-Uda antennas.
• Modification of a bandpass filter bank to meet MIR system requirements.
• Integration of a low-cost quadrature demodulator for phase detection.

Main Results:

• Successful development of essential MIR components: 2-D mixer array, modified bandpass filter bank, and quadrature demodulator.
• Significant reduction in development costs compared to traditional expensive waveguide systems.
• Demonstrated feasibility of using low-price commercial wireless devices for MIR.

Conclusions:

• The developed low-cost devices facilitate the creation of advanced 2-D/3-D microwave imaging systems.
• These advancements are applicable to plasma diagnostics in devices like the LHD.
• The technology holds potential for broader industrial imaging applications.