Digital Beamforming for a 3D MIMO SAR - Improvements through Frequency and Waveform Diversity

The 3D imaging and nadir looking ARTINO (Airborne Radar for Three-dimensional Imaging and Nadir Observation) principle uses a sparse MIMO antenna array distributed over the whole wings of an airplane. The adaption of the ARTINO principle to high and fast flying airplanes with large wings requires new concepts to deal with PRF limitations. In this paper, an extension of the ARTINO principle is presented based on two different strategies namely the frequency diversity and the waveform diversity. Both concepts allow the implementation of the ARTINO principle to arbitrary airborne platforms.