Experimental Study Of Multi-channel Correlation Reflectometry On EAST

This thesis is based on the design and test of the multi-channel correlation reflecto-metry system on EAST.Moreover,relevant data processing methods are summarized.Based on the knowledge and experiences of design of the microwave diagnostics,re-search and design activities facing CFETR is initiated.The multi-channel reflectometry system deployed on EAST contains a eight channels V band and a four channel W band correlation reflectometry working in X mode polarization.The probing frequencies are 50,54,58,60,62,64,68,72,79.2,85.2,91.8 and 96GHz which correspond to different radial locations.The antennae array of the system consists of two poloidally separated receiving antennae.Moreover,performance of the key components are test.The per-formance of the system is test in lab using the metal plate and the rotation simulator.Using the developed correlation reflectometry system,coherent mode in the ELM-free phase after the L-H transition with a plasma current of Ip = 400 kA is observed and analyzed in detail.The coherent mode localized at the steep gradient region of pedestal.Using the poloidal coherence calculation,the poloidal wavenumber k? is determined to be 0.5 to 0.7 cm-1.It rotates in the electron diamagnetic direction.The appearance of coherent mode is strongly correlated with the pedestal pressure,which indicates that the coherent mode is driven by pressure.Due to the shift of the probing position of the system induced by the evolution of the pedestal in between ELMs,characteristics of broad band fluctuations are carefully analyzed with the correlation reflectometry.At the pedestal region,the k? is 0-3 cm-1 and the fluctuations rotate in the electron diamagnetic direction.However,at the core region just inside the pedestal shoulder,the absolute poloidal wavenumber is similar yet the fluctuations rotate is a reversed direction,namely ion diamagnetic direction.A high frequency electromagnetic mode is observed using the correlation reflectometry and high frequency Mirnov coils with a frequency 400-500 kHz during the ELM-free phase after the L-H transition and in between the first and the second ELMs with Ip = 600 kA.Using the correlation analysis techniques,the toroidal mode number is identified to be 3-4 and rotates in the electron diamagnetic direction.The last part of the thesis is the research and design acti-vities facing the CFETR based on the newly developed 0D scenarios.The design of the reflectometry focuses on the selection of the frequency and polarization of the system and the radial coverage calculation of the system.Besides,properties of the electron cyclotron emission(ECE)system including the location and width of emission layers as well as the spatial resolution of the system.Moreover,new diagnostics techniques are exploring on EAST,such as the optical coupler based on the FSS,wide band low loss transmission system,and the reflectometry for plasmas in divertor region.