"JOURNAL OF RADIO ELECTRONICS" (Zhurnal Radioelektroniki ISSN 1684-1719, N 8, 2018

contents of issue      DOI  10.30898/1684-1719.2018.8.11     full text in Russian (pdf)  

Algorithms of autofocusing two dimensional ISAR images


S. I. Moryakov, S. M. Nesterov, I. A. Skorodumov

Central Research Institute of troops aerospace defense Ministry of Defense of the Russian Federation


The paper is received on August 3, 2018


Abstract. The inverse synthetic aperture radar systems are widely applied in many fields, like space and air control systems, special research laboratories and outdoor measurements facilities. To provide well-focused inverse synthetic aperture radar images we need to compensate translational and rotational phase shifts. This effort is also called range alignment and autofocusing. Autofocusing techniques provide to compensate nonlinear motion errors of the object. Many autofocus algorithms have been proposed over the years, ranging from quantitative measurement of residual errors to qualitative visual comparison. However, different data sets and motion errors were employed, it is difficult to perform comparative studies on various algorithms. In this paper a is observed a few of known autofocusing algorithms based on minimizing image entropy and phase gradient technics applied to experimental research in inverse synthetic aperture imaging techniques. Comparison of autofocusing algorithms was carried out on the mathematical model developed by the authors. As quality metrics for assessing algorithms performance were chosen: the minimum image entropy, correlation with the standard, computing complexity and work duration. As the result we can recommend these algorithms to various practical cases in air control, measurement facilities or laboratories efforts. In conclusion our study is that the algorithms based on minimum entropy provide the better performance results in most cases.

Key words: inverse synthetic aperture, radar images, nonparametric autofocusing.


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For citation:
S. I. Moryakov, S. M. Nesterov, I. A. Skorodumov. Algorithms of autofocusing two dimensional ISAR images. Zhurnal Radioelektroniki - Journal of Radio Electronics. 2018. No. 8. Available at http://jre.cplire.ru/jre/aug18/11/text.pdf

DOI  10.30898/1684-1719.2018.8.11