A water-based conical blackbody concept for millimeter-wave remote sensing

We propose a novel concept for water-based black-bodies to be used as calibration sources in microwave remote sensing instruments. In order to obtain a low electromagnetic reflectivity, a curved conical interface between water and air has been developed by means of numerical simulations. A blackbody prototype consisting of a 3D printed conical low-loss plastic shell was manufactured and experimental results demonstrate that the reflectivity of the proposed prototype is superior to established blackbody concepts. In particular, the S 11 is below −60 dB in the considered frequency ranges between 150 and 400 GHz.