Nadir-Looking Synthetic Aperture Radar (NadirSAR)

NadirSAR imaging offers a means to detect targets in challenging environments. TSC and SDL propose to leverage the work we have already performed for RRTO to develop and demonstrate a NadirSAR imaging technique at X-band. TSCs baseline technique exploits range resolution for height and performs SAR Tomographic processing around a circular flight path to obtain resolution in the ground plane. Measured data that has already been collected at nadir-looking angles of ~80 to 85 degrees in areas of light foliage and urban canyons will be used for algorithm development and testing. In Phase I, our team will mature this baseline technique to achieve the required resolution and investigate sparse SAR reconstruction techniques based on recent research at SDL. More advanced techniques and novel flight trajectories will also be investigated by TSC. In Phase I, computer simulation will be employed to evaluate the NadirSAR performance for different flight trajectories. Upgrades to the FlexSAR testbed will also be designed to support future Ku-band radar data collections. In Phase II, our team will collect Ku-band data and demonstrate reliable approaches that provide 3-D imagery in minimum time. Further work includes implementing real-time processing software and transitioning the algorithms into Army programs of record.