Process to generate a synthetic diagnostic for microwave imaging reflectometry with the full-wave code FWR2D

Area of Science:

• Plasma Physics
• Fusion Energy Research
• Diagnostic Development

Background:

• Microwave Imaging Reflectometry (MIR) is crucial for diagnosing plasma properties in fusion devices.
• Accurate modeling is essential for designing and interpreting MIR systems, especially for small-scale fluctuations.
• Existing methods may require enhancement for detailed analysis of plasma profiles.

Purpose of the Study:

• To introduce and validate a synthetic diagnostic tool, the full-wave reflectometer code (FWR2D), for MIR system design.
• To assess the capability of FWR2D in generating realistic synthetic diagnostic signals.
• To quantify the imaging quality of MIR for diagnosing plasma density fluctuations.

Main Methods:

• Development of the full-wave reflectometer code (FWR2D) for synthetic diagnostic signal generation.
• Integration of FWR2D with optical simulation tools using real plasma profiles as input.
• Comparison of synthetic signals with prescribed density fluctuation spectra to evaluate imaging performance.

Main Results:

• The FWR2D code successfully generates synthetic MIR signals using realistic plasma profiles.
• MIR, guided by FWR2D, demonstrates suitability for diagnosing density fluctuations with poloidal wavenumbers up to 2.0 cm⁻¹.
• The system can detect fluctuation amplitudes as low as 5%.

Conclusions:

• The synthetic MIR diagnostic tool (FWR2D) is a valuable asset for guiding the design of real MIR systems.
• FWR2D enables accurate simulation and analysis of MIR performance in complex plasma environments like the DIII-D tokamak.
• MIR is confirmed as a capable diagnostic for studying small-scale turbulence in fusion plasmas.