Autofocus for 3D Imaging with Multipass SAR

The emergence of 3D imaging from multipass radar collections motivates the need for 3D autofocus. While several effective methods exist to coherently align radar pulses for 2D image formation from a single elevation pass, further methods are needed to appropriately align radar collection surfaces from pass to pass. We propose one such method of 3D autofocus involving the optimization of a coherence factor metric for the dominant scatterers in an image scene. This method is demonstrated using a diffuse target from a multipass collection of circular SAR data.