一种基于天线指向的大方位扫描滑聚模式星载SAR几何定位技术

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中图分类号：TN958 文献标志码：A DOI：10.12305/j.issn.1001-506X.2026.03.12

A geometric positioning technology based on antenna pointing for large azimuth scanning sliding-spot mode of spaceborne SAR

LI Yingying*，WU Hao， CHEN Feng， LIN Yuzhuoyue， WANG Xueying， FENG Xin（Beijing InstituteofRemote SensingInformation，Beijingl0ool1，China）

Abstract：Because of the dechirp operation in the imaging algorithm of the sliding-spot mode，it is difcult to construct a rigorous range-Doppler equation for its geometric processing.In regard tothis，aconformation model based on synthetic aperture radar（SAR）antenna pointing vector is presented，which fullyconsidering the influence of the dechirp operationon the sliding-spotimaging.Starting fromtherelative position betweentheimage pointsofeachscaning line in SAR images and the satelite，based onaccurate satelite-to-ground geometric conditions，astrict transformation model betweenimage pointcoordinates and geographiccoordinates isestablished.Basedonthis model，the forward and inverse solution processs for SAR geometric positioning in sliding modeare given.Finaly，geometriccalibration and positioning processing experiments using diferent pulse width combinations anddiferent field data showed that after compensating for various geometric errorscausedbythe SARpayloaditself，atmospheric transmission，platformorbit position，elevation， and other factors， the uncontrolled geometric positioning accuracy of the sliding-spot image can reach 1-2m ，fully demonstrating the efectivenessof the proposed method in the geometric positioning of sliding-spot images.

Keywords： synthetic aperture radar （SAR）； sliding-spot imaging；dechirp；range-Doppler （RD）； geometric positioning

0 引言

星载合成孔径雷达（syntheticaperture radar，SAR）卫星影像的几何定位精度是影响其应用效能的核心要素之一，确保影像定位的准确性已成为该领域亟待攻克的技术重点。（剩余19570字）