| An innovative plasma diagnostic technique, electron cyclotron emission imaging (ECEI), has been successfully developed and implemented for the study of fusion plasma electron temperature profiles and fluctuations. The proof-of-principle 128-channel Electron Cyclotron Emission Imaging (ECEI) system installed on the TEXTOR device has produced exciting results in the areas of magnetic reconnection, suppression of magnetic islands by means of Electron Cyclotron Resonance Heating (ECRH), and imaging of meso-scale structures.;This dissertation research has focused on the development of the electronics for the next generation of ECEI systems, which are under development for use on tokamak magnetic fusion devices around the world. Specifically, the author has worked on the simulation, design, fabrication, and characterization of new RF electronics for ECEI systems to be installed on the TEXTOR tokomak (Julich, Germany) and the DIIID tokomak (San Diego, California). The new electronics was developed in two stages and considerably improves upon the original ECEI electronics and eliminates meaning of its limitations.;The first upgraded RF electronics realized an "all-on-one board" circuit with much less loss more compactness and simplified the entire system architecture. Also, the bandwidth was extended to 6.4 GHz, which represents a 60% increase and translates into increased, instantaneous spatial coverage. Together with other upgrades such as a new antenna array, the system was installed at TEXTOR in February 2007.;The second upgrade--dual-band RF electronics, provides a horizontal "zoom" capability for imaging, together with other upgrades in ECEI developed by other group members such as a new mini-lens array, new vertical-zoom optics and new multi-element ECRH filtering will extend the ECEI capability by permitting imaging in the presence of high power gyrotron heating. In addition, a new remote digital control system has been designed and realized with LabVIEW program, data acquisition device and digital circuit design. It is expected to become a standard control section for all ECEI systems. |
