A Simple Algorithm for Compensation for Range Cell Migration in a Stripmap SAR
https://doi.org/10.32603/1993-8985-2021-24-2-27-37
Abstract
Introduction. Range Cell Migration (RCM) is a source of image blurring in synthetic aperture radars (SAR). There are two groups of signal processing algorithms used to compensate for migration effects. The first group includes algorithms that recalculate the SAR signal from the "along–track range – slant range" coordinate system into the "along-track range – cross-track range" coordinates using the method of interpolation. The disadvantage of these algorithms is their considerable computational cost. Algorithms of the second group do not rely on interpolation thus being more attractive in terms of practical application.
Aim. To synthesize a simple algorithm for compensating for RCM without using interpolation.
Materials and methods. The synthesis was performed using a simplified version of the Chirp Scaling algorithm.
Results. A simple algorithm, which presents a modification of the Keystone Transform algorithm, was synthesized. The synthesized algorithm based on Fast Fourier Transforms and the Hadamard matrix products does not require interpolation.
Conclusion. A verification of the algorithm quality via mathematical simulation confirmed its high efficiency. Implementation of the algorithm permits the number of computational operations to be reduced. The final radar image produced using the proposed algorithm is built in the true Cartesian coordinates. The algorithm can be applied for SAR imaging of moving targets. The conducted analysis showed that the algorithm yields the image of a moving target provided that the coherent processing interval is sufficiently large. The image lies along a line, which angle of inclination is proportional to the projection of the target relative velocity on the line-of-sight. Estimation of the image parameters permits the target movement parameters to be determined.
About the Author
A. A. Monakov
Saint Petersburg State University of Aerospace Instrumentation (SUAI)
Russian Federation
Russian Federation
Andrey A. Monakov, Dr. Sci. (Eng.) (2000), Professor (2005) of the Department of radio equipment systems, Honorable Mechanical Engineer of the Russian Federation (2005), Honorable Worker of Higher Professional Education of the Russian Federation (2006). The author of more than 150 scientific publications. Area of expertise: digital signal processing; radar theory; microwave remote sensing; air traffic control.
67A Bolshaja Morskaja St., St Petersburg 190121
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For citations:
Monakov A.A. A Simple Algorithm for Compensation for Range Cell Migration in a Stripmap SAR. Journal of the Russian Universities. Radioelectronics. 2021;24(2):27-37. https://doi.org/10.32603/1993-8985-2021-24-2-27-37
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