A novel focusing technique for ISAR in case of uniform rotation rate

A method for the correction of Migration Through Resolution Cells (MTRC) in ISAR (Inverse Synthetic Aperture Radar) is addressed here. The new technique needs neither to know the target motion parameters, to estimate them nor to use optimization to maximize (minimize) an image focusing indicator. It assumes that the target rotation rate is uniform and the direction of the effective rotation vector does not change during the Coherent Processing Interval (CPI). The algorithm corrects the MTRC in two phases: Slant Range Rotation Compensation (SRRC) and Cross Range Rotation Compensation (CRRC), where CRRC is based on an extension of the Phase Difference method (PD). The effectiveness of the proposed technique is verified with simulated (MIG-25 aircraft) and real (sailboat) radar data and compared with the standard Range-Doppler Algorithm (RDA).