One-station fixed two-station SAR imaging method based on full resolution range model

Abstract

The invention discloses a full-resolution range model-based one-stationary bistatic SAR (synthetic aperture radar) imaging method. The method of the invention include the following steps that: 1, a one-stationary bistatic SAR system geometric model is accurately constructed, and echo signals are obtained; 2, range-direction pre-processing is performed on the signals in a range frequency domain; 3,a new full-resolution range model is constructed according to the result of the range-direction processing, and azimuth space-variation characteristics between point targets which are located on thesame range unit and distributed along an azimuth direction and the center distance of a receiver can be accurately described; and 4, accurate modeling is performed for the azimuth space-variation characteristics of complex Doppler phases according to the new full-resolution range model, and azimuth equalization is realized through an ENLCS algorithm, a filter is designed to perform azimuth compression, and a final focused image is obtained. The method of the invention enables a better focusing effect in processing the high-resolution echo data of a large-squint one-stationary bistatic SAR.

Description

technical field [0001] The invention belongs to the field of signal processing, and relates to a high-resolution imaging processing algorithm of a one-station fixed dual-station synthetic aperture radar. Specifically, a brand-new azimuth full-analysis distance model is proposed on the basis of range processing, which accurately describes multiple The azimuth-space-variant characteristics of the Puller phase, and thus improve the method of applying the ENLCS (Extended Nonlinear Chirp Scaling) algorithm in the azimuth direction for imaging processing. Background technique [0002] The idea of ​​constructing an equivalently long antenna through signal processing technology is called Synthetic Aperture Radar (SAR, Synthetic Aperture Radar). In remote sensing, SAR obtains surface images with the help of airborne or spaceborne platforms. This process uses the radar beam to transmit phase-modulated pulses in a direction that is nearly perpendicular to the movement of the sensor or ...

AI Technical Summary

Problems solved by technology

The currently commonly used analytical methods either directly apply the range-azimuth analytical model of single-station SAR, or propose some improved models on this basis, but such methods generally cannot obtain closed solutions, resulting in insufficient accuracy of the model. High-resolution imaging processing that cannot be applied to one-station fixed dual-station SAR

The commonly used numerical methods are generally curve fitting method or numerical integration method, but this type of method requires a large amount of calculation and cannot be applied to real-time imaging processing

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