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Updated: Jan 28, 2026
10:26
Fabrication and Characterization of Superconducting Resonators
Published on: May 21, 2016
11.9K
Five-channel tunable W-band Doppler backscattering system in the experimental advanced superconducting tokamak
1KTX Laboratory and Department of Engineering and Applied Physics, University of Science and Technology of China, Anhui, Hefei 230026, China.
The Review of Scientific Instruments
|March 6, 2019
Summary
A new 5-channel Doppler backscattering system was installed on the Experimental Advanced Superconducting Tokamak (EAST). This system measures plasma properties using a tunable W-band frequency, enhancing fusion energy research.
Area of Science:
- Plasma physics
- Fusion energy research
- Microwave diagnostics
Background:
- Tokamaks require advanced diagnostics to understand plasma behavior.
- Doppler backscattering is a key technique for measuring plasma density and turbulence.
- The W-band frequency range offers advantages for plasma density measurements.
Purpose of the Study:
- To design and implement a novel 5-channel Doppler backscattering system for the EAST tokamak.
- To enable detailed measurements of plasma properties within the W-band frequency range.
- To validate the system's performance through ray tracing and preliminary plasma experiments.
Main Methods:
- Utilized an I/Q-type double sideband modulator and frequency multiplier to create a 1.6 GHz frequency array.
- Developed a tunable W-band (75-97.8 GHz) system with adjustable incident angles (-4° to 12°).
- Employed ray tracing for accurate calculation of scattering location and wavenumber (4-15 cm⁻¹, resolution Δk/k ≤ 0.35).
Main Results:
- Successfully designed and installed a 5-channel Doppler backscattering system on EAST.
- Generated a finely spaced frequency array (Δf = 400 MHz) tunable within the W-band.
- Demonstrated capability for measuring plasma parameters with specified wavenumber resolution.
Conclusions:
- The new Doppler backscattering system is a valuable diagnostic for EAST.
- The system's design and capabilities are suitable for detailed plasma physics studies.
- Preliminary results indicate the system's potential for advancing fusion energy research.
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