An Integrated Radar Tile for Digital Beam Forming X/Ka Band Synthetic Aperture Radar Instruments

This work presents the first experimental assessment of a highly integrated dual-band dual-polarized antenna tile designed for Synthetic Aperture Radar (SAR) Digital Beam Forming (DBF) satellite applications. The demonstrator described in this paper is the first comprehensive experimental validation of an RF module providing X- and Ka band (9.6 and 35.75 GHz) operation with custom down-conversion stages. All the antennas, transitions and down-conversion chips are integrated in the same antenna tile fabricated using a customized 15 layer High Density Interconnect (HDI) process. The designed tile goes to the limits of the proposed technology and for the high trace density and for the size of the vertical transitions. The proposed results represent the state of the art in terms of compactness for a DBF SAR RF module even though the demonstrator was manufactured with a standard low cost technology. The experimental assessment proves the validity of the proposed manufacturing and integration approaches showing a substantial agreement between the performance of the individual blocks and of the integrated system