Method for super-resolution imaging of foresight array SAR based on sparse representation

Abstract

The invention discloses a method for super-resolution imaging of a foresight array SAR based on sparse representation. The method mainly solves the problems that an existing foresight imaging algorithm is difficult to achieve physically, and system cost is high. The method comprises the steps that (1) SAR echo data are received in a double-base mode, and echo signals are modified in a single-base mode; (2) range pulse compression and direction dimension unbinding and frequency modulation are conducted on the modified echo signals; (3) according to the observation scene and the sparse characteristic of an imaging target, a cost function of SAR imaging of the processed signals is established through the maximum posterior probability estimation method; (4) the updated quasi-Newton algorithm is used for solving the cost function, and then a super-resolution imaging result of the foresight array SAR is obtained. By means of the method, a high-resolution foresight imaging result can be obtained under the condition of a limited array length, the cost and complexity of a system are effectively lowered, and the method can be applied to target detection, topographic reconnaissance, guidance, city planning and environment surveys.

Description

technical field [0001] The invention belongs to the field of radar signal processing, in particular to SAR imaging of scenes directly in front of platform movement, and can be used for SAR imaging processing of airborne and spaceborne platforms. Background technique [0002] Synthetic aperture radar (SAR) imaging belongs to high-resolution imaging technology. In the radial distance, the resolution is improved by transmitting broadband signals, and in the azimuth, it is realized by relying on the movement of the radar platform to form a long linear array in space. Over the past half a century, SAR imaging technology and theoretical research have made great progress and have been widely used. [0003] Traditional SAR usually adopts the working mode of side view. There have been a lot of researches on SAR imaging processing in this mode, mainly relying on the Doppler information provided by the imaging platform relative to the target motion to achieve high resolution in the azi...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to address the deficiencies of the above-mentioned prior art, combined with the theory of compressed sensing widely used in recent years, to propose a forward-looking array SAR super-resolution imaging method based on sparse representation, to solve the physical problem of the existing forward-looking array SAR imaging algorithm. Difficult to implement and low resolution issues

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