A New Concept for SAR Image Quality Assessment Realizing Bar Patterns in SAR Images

Abstract:
Image quality assessment of SAR images is usually done by evaluating the signal of active or passive corner reflectors, as this signal is very close to the system point response. For Electro-Optical (EO) sensors bar patterns like tree bars are widely used and standardised for image quality assessment. At the FOM a concept was developed to realize bar patterns in SAR images. A Test Field was constructed creating the necessary contrast by different surface roughness. This Test Field was recorded with the very high resolution SAR-Sensor PAMIR developed and operated by the FHR. The minimum dimensions of the Test Field are related to the considered spatial resolution of the sensor system. The sub-decimeter resolution provided by the PAMIR-system allowed to build the Test Field for this feasibility study with low effort and minimal cost. The first SAR images show that the bar patterns can be clearly identified. Furthermore, the contrast modulation achieved by the roughness variations was very successful for this purpose. Bar patterns allow an image quality assessment even by non-specialists and additionally this concept builds a bridge to image assessment procedures commonly used for EO sensors.