SAR echo rapid time domain generation method

Abstract

The invention discloses an SAR echo rapid time domain generation method. All point targets included by a surface target are merged stage by stage, each merged group of point targets at each stage are replaced with one virtual point target, first-stage echoes are generated by use of a time domain superposition method, as the point targets are merged stage by stage, sub echoes generated at each stage gradually become dense, finally, when the number of sampling points in an echo data orientation becomes the same as the number of orientation sampling points, merging ends, and complete echoes are obtained by superposing sub echoes of the last stage. Compared to a conventional time domain superposition method, the method provided by the invention has the following advantages: the orientation sampling points and the point targets do not have to be traversed one by one, the calculation redundancy generated by the echoes is reduced, the computation amount is greatly reduced, the method is applied to an SAR system of any mode and is especially applied to echo generation of a large-scene surface target, and at the same time, platform motion errors are easily introduced.

Description

technical field [0001] The invention belongs to the technical field of radar, and in particular relates to an echo time-domain generating method in the SAR imaging technology. Background technique [0002] SAR is an all-day, all-weather modern high-resolution microwave remote sensing imaging radar. It uses the relative motion between the radar antenna and the target area to obtain high resolution in the range direction, and uses pulse compression to obtain high resolution in the range direction. In the fields of military reconnaissance, terrain surveying and mapping, vegetation analysis, ocean and hydrological observation, environment and disaster monitoring, synthetic aperture radar has played an increasingly important role. [0003] SAR echo generation technology refers to reproducing the working process of synthetic aperture radar by establishing a model and using computer simulation to obtain simulated echo data. Because SAR data processing and imaging processing equipm...

AI Technical Summary

Problems solved by technology

However, the frequency-domain echo generation methods are all based on the azimuth-space invariant assumption, and can only be applied to the single-base SAR mode and the shift-invariant bistatic SAR mode of uniform linear motion. Echoes simulated by bit frequency domain analysis are inaccurate

Images