【摘 要】
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For ship targets with complex motion, it is difficult for the traditional monostatic inverse synthetic aperture radar (ISAR) imaging to improve the cross-range resolution by increasing of accumulation time. In this paper, a distributed ISAR imaging al-gor
【机 构】
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School of Electronics and Information Engineering,Harbin Institute of Technology,Harbin 150001,China
论文部分内容阅读
For ship targets with complex motion, it is difficult for the traditional monostatic inverse synthetic aperture radar (ISAR) imaging to improve the cross-range resolution by increasing of accumulation time. In this paper, a distributed ISAR imaging al-gorithm is proposed to improve the cross-range resolution for the ship target. Multiple stations are used to observe the target in a short time, thereby the effect of incoherence caused by the complex motion of the ship can be reduced. The signal model of ship target with three-dimensional (3-D) rotation is constructed firstly. Then detailed analysis about the improvement of cross-range resolution is presented. Afterward, we propose the me-thods of parameters estimation to solve the problem of the over-lap or gap, which will cause a loss of resolution and is neces-sary for subsequent processing. Besides, the compressed sens-ing (CS) method is applied to reconstruct the echoes with gaps. Finally, numerical simulations are presented to verify the effect-iveness and the robustness of the proposed algorithm.
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