https://www.nist.gov/publications/use-high-temperature-integrating-sphere-reflectometer-surface-temperature-measurements
NIST has developed a new facility for the characterization of the infrared spectral emissivity of samples between ambient and 1000 C.
integrating sphereusehightemperaturereflectometer
https://www.nist.gov/publications/wideband-measurement-extreme-impedance-multistate-reflectometer
Abstract: We present a technique for accurate wideband measurements of one-port devices with extreme impedances.
widebandmeasurementextremeimpedancereflectometer