Design and development of ground calibration targets for the MetOP-SG microwave sounder payload

We report on the reflection properties of calibration targets required for calibrating the radiometric performance of the Microwave Sounder instruments for the MetOp-SG satellites prior to launch. Both fixed temperature, 80 K, and variable temperature, 80–315 K, targets are required to perform this task. The specifications, the preliminary baseline design of the target structure and its measured reflectivity are presented in this paper.