Microwave Imaging Reflectometry from concept to construction: The role of modeling and laboratory characterization in diagnostic development

Summary form only given. Microwave Imaging Reflectometry (MIR) is a novel and ambitious application of reflectometry with a potential to revolutionize the diagnosis of tokamak plasma phenomena¹, particularly electron density fluctuations. By adapting the principles of 2D millimeter wave imaging which have done so much to advance heterodyne radiometry through the development of ECE Imaging, MIR promises to provide the experimentalist with a truly unique dataset and new opportunities for exploring the polarization and 2D structure of turbulence, the physics of acoustically coupled instabilities, and the evolution of shear flows whose influence may dominate the confinement properties of high performance tokamak discharges. A collaboration between UC Davis and the Princeton Plasma Physics Laboratory brings together a wealth of expertise in millimeter wave technology and plasma simulation. The development of quasi-optical solutions from steerable phased antenna arrays with low noise monolithic microwave integrated circuit (MMIC) amplification schemes to large aperture planar frequency selective surface (FSS) filters for sideband selection and system protection is closely coupled to synthetic diagnostic modeling which includes a sophisticated representation of the imaging optics and a fullwave simulation of the plasma-wave interaction courtesy of the FWR2D code². Recent progress in the development of MIR technology and diagnostic techniques will be discussed, providing the audience with an appreciation for both the potential of this technique and the challenges faced in bringing a robust diagnostic system to the scientific community.