Inverse synthetic aperture radar imaging distance aligning method applicable to low signal-noise ratio data

Abstract

The invention relates to a method of range alignment in inverse synthetic aperture radar (ISAR) imaging, which is applicable to low signal-to-noise ratio data. The method directly corrects the target linear range walk by Keystone transformation, the transformation can be realized by linear interpolation, the computation amount is low, and the robustness is good under the low signal-to-noise ratio condition; as for the range walk problem of a quadratic term caused by target radial acceleration, firstly coherent accumulation of the adjacent range images is performed to obtain a high signal-to-noise ratio synthetic range image, and then an estimated value of the radial acceleration is searched to maximize the corrected kurtosis value of the quadratic sum of various range images after time delay adjustment; the radial acceleration search which takes the corrected kurtosis value as an index has overall significance, and the anti-noise performance is good. In the method, only one-dimensional search is needed instead of high-dimensional search, thus the computation amount is low.

Description

technical field [0001] The invention relates to an inverse synthetic aperture radar (ISAR) imaging distance alignment method suitable for low signal-to-noise ratio data, in particular to an ISAR imaging distance alignment method suitable for smooth flying target low signal-to-noise ratio echo data. Background technique [0002] Inverse synthetic aperture radar can perform all-weather, all-time, and long-distance imaging of moving targets such as missiles, satellites, ships, and celestial bodies from fixed or moving platforms. It is important in strategic defense, anti-satellite, tactical weapons, and radar astronomy. Value. Inverse synthetic aperture radar is based on the principle of range-Doppler imaging. In this imaging method, the radar does not move, but the moving target is equivalent to a rotating platform target rotating at a constant speed. In a small viewing angle range, the scattering of the target The properties can be approximated by a series of scatter points ...

AI Technical Summary

Problems solved by technology

Someone proposed a distance alignment technology based on Hough transform, which has certain anti-noise performance and good robustness, but it is often difficult to meet the accuracy requirements of ISAR imaging processing distance alignment in the case of low signal-to-noise ratio.

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