An Improved ffbp Imaging Method for Efficient Global Cartesian Coordinate Projection Fusion

Abstract

The invention belongs to the technical field of SAR imaging, and discloses an improved FFBP imaging method for high-efficiency global Cartesian coordinate projection fusion, comprising the following steps: using synthetic aperture radar to receive echo signals, performing range-wise matching filtering on them, and obtaining range-compressed Signal; establish a global Cartesian coordinate system with the center of the synthetic aperture as the origin, and divide the full aperture data into N sub-aperture data evenly after distance compression; construct a global Cartesian coordinate projection grid in the imaging area, and place each sub-aperture data in the global Cartesian coordinates The sub-aperture imaging results are obtained by back-projecting on the projection grid; under the global Cartesian coordinate projection grid, the sub-aperture imaging results are recursively fused to obtain a full-aperture high-resolution image; this method breaks through the traditional FFBP algorithm based on local The limitation of the polar coordinate grid makes full use of the advantages of global rectangular coordinate grid projection and recursive fusion, avoids two-dimensional point-by-point interpolation and coordinate conversion, and has high processing efficiency.

Description

Technical field [0001] The present invention relates to the field of synthetic Aperture Radar, SAR) imaging, and specific to an improved FFBP imaging method for efficient global right-angle coordinate fusion, which can be used for SAR imaging processing platforms such as airborne, suitable for various complex imaging. High precision real-time imaging. Background technique [0002] The time domain rear projection (BP) imaging algorithm is added to coherence and coherence, and precise imaging in arbitrary tracking and radar mode is achieved. However, the time domain is highly complex to projection imaging algorithm, which limits its engineering applications in large-scale imaging. [0003] In order to increase the efficiency of the projection imaging algorithm, some fast time domain imaging algorithms are proposed in which the imaging algorithm is most representative of the FAST FACTORZED BP, FFBP. The FFBP algorithm utilizes a sub-aperture image angle domain sparse, generates a cr...

AI Technical Summary

Problems solved by technology

However, the fusion of subgraphs in different local polar coordinate systems relies on "point-to-point" two-dimensional interpolation, which brings a huge amount of computation and also leads to the accumulation of interpolation errors

In engineering applications, the imaging accuracy and efficiency of the FFBP algorithm are mutually restricted, and it is difficult to balance

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