Radiation Pattern Modulation Impact on Turntable Near-Field ISAR Images

The impact of the antenna radiation pattern on the quality of inverse synthetic aperture radar (ISAR) images is investigated for turntable near-field (NF) measurements. In particular, radar data are synthetically produced for a circular scan using a uniform and tapered illumination. From these radar data, ISAR images are produced using a NF processing including a compensation for path loss and the non-planar phase front of the incident wave. Results using a standard far-field (FF) ISAR processing are also reported. The produced ISAR images are compared in terms of different quality metrics, i.e., image entropy, contrast and energy. Finally, the radar cross section (RCS) of the target is extracted from the ISAR images and compared to a reference one.