The Advanced And Integrated Microwave Reflectometer Diagnostic System On EAST Tokamak

Microwave diagnostic systems play important roles in the plasma diagnosis as non-invasive techniques. The microwave reflectometer,a typical microwave diagnostic system, can provide many measurements with high spatial and temporal resolution for the fusion plasma, and now has a wider and wider use in the Magnetic confinement fusion devices. This dissertation is focused on the design, development and the experiments of the Advanced and Integrated Microwave Reflectometer Diagnostic System (AIMRDS) on EAST (Experimental Advanced Superconducting Tokamak)located in the Institute of Plasma Physics of Chinese academy of SciencesThe AIMRDS on EAST is organically integrated of an 8-channel Doppler Backscattering system (DBS8) and a two-frequency-band reflectometer for electron density profile measurement. The DBS8 and the profile reflectometer share a microwave quasi-optic frontend, and can provide complementary measurements of electron density profile, the radial distribution of the plasma poloidal rotation velocity,the radial electric field, turbulence intensity, turbulence wavenumber spectrum, and other measurements of fusion plasma, which can help characterizing the mode of the turbulence and studying the mechanism of the transport and confinement, the L-H mode transition and other problems of fusion plasma physics.In its part of data analyzing, this dissertation discusses about the theoretical,experimental and numerical simulation methods in detail. The density inversion methods, density fluctuation effects, relativistic effect, error field effect, 'Doppler Effect', pitch angle coupling and precautions related to zero density point are discussed for the profile reflectometer. And for the DBS8, several methods of the calculation of frequency shift and mode analysis are introduced. Finally, a discussion on the Precautions about the sampling clocks in mode analysis and a numerical simulation on the SOL effect on the optical path are Carried out.The main part of this dissertation, the detail process of design, construction,calibration and testing of AIMRDS on EAST is introduced particularly. This system includes a common quasi-optical transceiver front-end, dual-band (Q-band, 33-50GHz and V-band, 50-75GHz) dual-polarization (O-mode and X-mode) continuous wave modulation (FMCW) ultrafast sweeping monostatic homodyne profile reflectometer and 8-channel monostatic heterodyne Doppler backscatter system (8 DBS) which can simultaneously measure eight locations of frequencies (55,57.5,60, 62.5, 67.5, 70,72.5 and 75 GHz) . In addition, a detailed description of the supporting subsystems: data acquisition and storage systems, protection systems, temperature control systems,mirror drive and monitoring systems, power supply systems and other subsystems. The design, calibration and testing of these subsystems are given, especially the quasi-optical tests, VCO linearization and dynamic calibration, 8 DBS commissioning and frequency-shift calibration tests by rotating grating wheels. Finally we introduced the new testing and calibrating platform developed to build and test this integrated reflectometers.At the end of this paper, some basic results of the actual measurement in the EAST discharge experiment are given, including the electron density profile distribution, the evolution of the pedestal and the experimental results of the 8 DBS system during the L-/H-mode and the low-hybrid-wave heating discharge, verifying the measurement capabilities of this reflectometer system.