SAR image quality assessment and indicators for airport detection

The airport detection based on the Synthetic aperture radar (SAR) image is of great importance for both military and civil applications. Typically, the airport is characterized by the airport runway appearing as the black elongated rectangle in the SAR image. The airport detection, which aims to find the elongated rectangles with specific length and width, poses high demands on the spatial resolution and the radiometric resolution. Thus, the performance of the airport detection depends to a large extent on the SAR image quality. Generally, the image quality indicators are measured to check whether the image is compliant to the system specifications. However, such compliance is not 1:1 related to whether the image is suitable for a specific application. In this paper, we summarize SAR image quality indicators and introduce the concept of application suitability. Furthermore, we propose the Requirement and Tolerance values of each quality indicator for the airport detection application, based on the analysis over a set of images from different SAR sensors and SAR modes. Finally, the proposed method is applied to a 1-m Terra-SAR image of Shanghai Pudong International airport to verify its practical applicability.