High squint synthetic aperture radar imaging processing method

Abstract

The invention discloses a high squint synthetic aperture radar imaging processing method, which comprises the steps of S1, calculating high squint synthetic aperture radar echo signals; S2, carrying out range fast Fourier transformation (FFT) and spatial-variant range walk correction on the echo signals, and removing range spatial-variant range walk; S3, carrying out range pulse compression and high-order range migration correction on the echo signals, and removing residual range migration; S4, carrying out azimuth spatial-variant property fitting of Doppler parameters on the echo signals; S5, balancing the Doppler centroid and the slope of frequency modulation of target points of the same range cell by adopting an extended azimuth nonlinear frequency modulation scaling algorithm; and S6, carrying out azimuth focusing so as to acquire an imaging result. The high squint synthetic aperture radar imaging processing method solves a range spatial-variant property and an azimuth spatial-variant property of the Doppler parameters, can realize precise focusing of monostatic SAR echo signals under a high-squint-angle condition, and can be widely applied to the fields of earth remote sensing, resource exploration, geological mapping, military reconnaissance and the like.

Description

technical field [0001] The invention belongs to the technical field of radar, and in particular relates to a high squint synthetic aperture radar imaging processing method. Background technique [0002] Synthetic Aperture Radar (SAR) is an all-weather, all-weather high-resolution imaging system. By transmitting a chirp signal with a large time-width bandwidth product, a pulse compression signal is obtained by matching filtering during reception, so as to obtain a range-wise high-resolution imaging system. , using synthetic aperture technology to achieve high resolution in azimuth. The imaging quality is not affected by weather conditions (clouds, light), etc., and has the characteristics of detecting and locating long-distance targets. Typical applications of SAR include disaster monitoring, resource exploration, geological surveying and mapping, military reconnaissance, etc. [0003] Compared with the front side view, the airborne SAR squint imaging has good flexibility a...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to overcome the disadvantages of low accuracy caused by the range-to-space variability of range migration and the azimuth space-to-space variability of Doppler parameters in the prior art, and provide a single-static SAR echo that can realize a large oblique angle of view. The precise focusing can be widely used in high squint synthetic aperture radar imaging processing methods in the fields of earth remote sensing, resource exploration, geological mapping, military reconnaissance, etc.

Images