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An Analysis of ISAR Image Distortion Based on the Phase Modulation Effect

EURASIP Journal on Advances in Signal Processing volume 2006, Article number: 083727 (2006) Cite this article

Abstract

Distortion in the ISAR image of a target is a result of nonuniform rotational motion of the target during the imaging period. In many of the measured ISAR images from moving targets, such as those from in-flight aircraft, the distortion can be quite severe. Often, the image integration time is only a few seconds in duration and the target's rotational displacement is only a few degrees. The conventional quadratic phase distortion effect is not adequate in explaining the severe blurring in many of these observations. A numerical model based on a time-varying target rotation rate has been developed to quantify the distortion in the ISAR image. It has successfully modelled the severe distortion observed; the model's simulated results are validated by experimental data. Results from the analysis indicate that the severe distortion is attributed to the phase modulation effect where a time-varying Doppler frequency provides the smearing mechanism. For target identification applications, an efficient method on refocusing distorted ISAR images based on time-frequency analysis has also been developed based on the insights obtained from the results of the numerical modelling and experimental investigation conducted in this study.

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Authors and Affiliations

  1. Defence R&D Canada - Ottawa, 3701 Carling Avenue, Ottawa, ON, K1A 0Z4, Canada

    S. K. Wong, E. Riseborough & G. Duff

Authors
  1. S. K. Wong
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  2. E. Riseborough
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  3. G. Duff
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Correspondence to S. K. Wong.

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Open Access This article is distributed under the terms of the Creative Commons Attribution 2.0 International License ( https://creativecommons.org/licenses/by/2.0 ), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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Wong, S.K., Riseborough, E. & Duff, G. An Analysis of ISAR Image Distortion Based on the Phase Modulation Effect. EURASIP J. Adv. Signal Process. 2006, 083727 (2006). https://doi.org/10.1155/ASP/2006/83727

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  • DOI: https://doi.org/10.1155/ASP/2006/83727

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