Holographic Radar Signal Processing

The 3-D SAR imaging of objects in a scene provides improved military target identification and weapons targeting accuracy. This capability can also potentially be combined with simultaneous SAR/GMTI surveillance modes to provide 3-D context information for moving targets in a scene. In Phase I, TSC demonstrated a promising approach for noncoherently combining 3-D tomographic SAR images generated from data cubes collected on multiple circular orbits at different elevations. This approach significantly reduced layover and provided improved vertical discrimination of target features. TSC also investigated coherent processing techniques including summing phase-corrected and registered data from each orbit. SDL collected X-band data on multiple orbits on several flight tests using their NuSAR and NRL's RASAR L-band sensor. In Phase II, our team will collect additional X- and L-band SAR data and investigate several promising coherent and noncoherent processing techniques for generating 3-D Holographic SAR products, and overcoming sparse aperture limitations. TSC will evaluate the performance using metrics including vertical resolution and sidelobe levels. All of the developed algorithm software will be delivered, and can be customized for high performance processors or sensors such as the GOTCHA Spiral II radar. In addition, TSC will investigate Holographic SAR imaging using simultaneous SAR/GMTI modes.