Density measurements by microwave interferometer
Task outline
- Learn the basics of microwave interferometry at the GOLEM tokamak
- Learn digital data processing routines for calculating the electron density
- choose one algorithm from Fourier transform, 0-crossing, Hilbert transform
- Perform experiments focusing on electron density \(n_e\):
- \(n_e\) dependence on discharge parameters .. i.e. how to achieve target \(n_e(t)\)
- dependance of other discharge characteristics on different \(n_e(t)\)
Resources
- Diploma thesis by Lukas Matena includes:
- basic theory of plasma interferometry, MW propagation in plasma
- analog analysis circuit development
- comparison of digital algorithms based on the Fourier transform and 0-crossing
Example \(n_e\) calculation via the Fourier transform: signal demodulation page and the responsible Python code
Example and explanation of a generalized algorithm based on the Hilbert transform and comparison with the original one: folder