Wide-Band Microwave Components for a Tokamak Edge Scanning Reflectometer

The Edge scanning reflectometer designed for the SPARC tokamak requires several passive microwave waveguide components for operation. The low-loss, wide-band, in-vessel parts must operate within the tokamak, posing many challenges for materials and durability. A bandpass coupler was designed to enable in-situ calibration of the reflectometer, and a double window was designed for low-loss transmission into the tokamak vacuum. These components are implemented for two frequency ranges covering four bands cumulatively: K/Ka and U/E-band. Prototypes of both components have been tested and matched to electromagnetic simulations with Ansys HFSS.