Aperture-coupled microstrip patch phased arrays in C- and X-band: a contribution to future multi-polarization multi-frequency SAR systems

Future spaceborne SAR systems will use active phased array antennas with multi-polarization and multi-frequency capabilities. For high resolution SAR images of high quality the antennas have to provide a large bandwidth and an extreme polarization purity. These requirements can be met by aperture-coupled microstrip patch phased arrays based on low-permittivity, low-weight and low-cost foam substrates. The paper presents their design and their measured performance in C-band (5.3 GHz) and X-band (9.6 GHz).