A novel SLC to GEO image generation approach and automatic control points conversion from GEO to SLC domain for SAR data quality evaluation and analysis

Abstract

This paper presents a novel and efficient approach for the generation of georeferenced (GEO) image from Single Look Complex (SLC) image and a procedure for automatic conversion of control points from GEO to SLC image. Using the proposed approach, the control points in one image can be transformed to the corresponding control points in other image with subpixel accuracy. Automatic transformation of control points from GEO to SLC domain is an essential requirement in many of the Geometric Data Quality Evaluation (GDQE) and Radiometric Data Quality Evaluation (RDQE) activities. One of the main reason for control point transformation is that it is difficult to identify control points in SLC image due to its orientation, distortion and geometry of slant range SAR data. The proposed approach is also made operational in ISRO’s Data Quality Evaluation (DQE) software and is extensively applied for GDQE/RDQE evaluations on SAR data products.