Synthetic Aperture RADAR (SAR) is a radar imaging technique in which the relative motion of the sensor is used to synthesize a very long antenna and obtain high spatial resolution. The increasing interest of the scientific community to simplify SAR sensors and develop automatic system to quickly obtain a sufficiently good precision image is fostered by the will of developing low-cost/light-weight SAR systems to be carried by drones. Standard SAR raw data processing techniques assume uniform motion of the satellite (or aerial vehicle) and a fixed antenna beam pointing sideway orthogonally to the motion path, assumed rectilinear. In the same hypothesis, a novel blind data focusing technique is presented, able to obtain good quality images of the inspected area, in the presence of a strong point scatterer, without the use of ancillary data information. Despite SAR data processing is a well established imaging technology that has become fundamental in several fields and applications, in this paper a novel approach has been used to exploit coherent illumination, demonstrating the possibility of extracting a large part of the ancillary data information from the raw data itself, to be used in the focusing procedure. Preliminary results – still prone to enhancements – are presented for ERS raw data focusing. The proposed Matlab software is distributed under the Noncommercial – Share Alike 4.0 – International Creative Common license by the authors.
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