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Use of Genetic Algorithms for Contrast and Entropy Optimization in ISAR Autofocusing


Image contrast maximization and entropy minimization are two commonly used techniques for ISAR image autofocusing. When the signal phase history due to the target radial motion has to be approximated with high order polynomial models, classic optimization techniques fail when attempting to either maximize the image contrast or minimize the image entropy. In this paper a solution of this problem is proposed by using genetic algorithms. The performances of the new algorithms that make use of genetic algorithms overcome the problem with previous implementations based on deterministic approaches. Tests on real data of airplanes and ships confirm the insight.


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Correspondence to Marco Martorella.

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Martorella, M., Berizzi, F. & Bruscoli, S. Use of Genetic Algorithms for Contrast and Entropy Optimization in ISAR Autofocusing. EURASIP J. Adv. Signal Process. 2006, 087298 (2006).

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  • Entropy
  • Genetic Algorithm
  • Image Contrast
  • Polynomial Model
  • Signal Phase