Diagnostics of the BIOMASS feed array prototype

The 3D reconstruction algorithm is applied to the prototype feed array of the BIOMASS synthetic aperture radar, recently measured at the DTU-ESA Spherical Near-Field Antenna Test Facility in Denmark. Careful analysis of the measured feed array data has shown that the test support structure of the array has a dominant influence on the measured feed pattern. The 3D reconstruction is then applied to the feed array measured data, allowing the identification of the undesired currents induced on the feed support structure. The results of the diagnostics and the corresponding improvements of the feed pattern obtained by removal of the undesired currents are presented and discussed.