ISAR image visualization for aerospace targets

Due to the large dynamic range and low contrast, inverse synthetic aperture radar (ISAR) image is not appropriate for human observation. In order to output and display the target imaging results, a procedure which compresses the dynamic range of the raw images into a lower range is necessary. In this paper, by analyzing the histogram of original ISAR images, the characteristics of ISAR images are investigated. Given the sparse amplitude distribution of original ISAR image and the shortcomings existing in the sparse linear histogram, this paper proposes an ISAR image detail enhancement algorithm (ISARIDE) based on histogram equalization and dynamic range compression. The advantage of the proposed method is that it can retain the target structure information, and improve the visual effect of human eye to target details as soon as possible. The proposed algorithm was tested on the simulated data and real data. The selected target is a flying Boeing 737-800.The results show the validity of the algorithm.