Migration of underground targets in UWB-SAR systems

Ultra-wideband synthetic aperture radar (UWB-SAR) systems can be used for imaging underground targets. However, conventional imaging algorithms that assume a constant velocity of propagation will exhibit degradations such as blurred targets and incorrect target locations. A superior approach is to do the processing by migrating the raw data collected by an array of sensors. In this paper, we use a filtering structure for migration as a 2-D all-pass filter, and present a practical processing method for UWB-SAR imaging. Improvements versus conventional SAR image focusing are included.