CAJ | 학술논문

窄波束和平地假设是在合成孔径雷达(SAR)运动补偿过程中常用的一种假设，其指明可以将SAR平台相对场景中任意点目标运动误差的空变近似为相同最短斜距处波束中心视线方向上相应点目标的距离空变。该文在正侧视模式和斜视模式运动补偿模型的基础上，从理论上证明了仅存在高度误差时，窄波束和平地假设运动补偿最优的方向垂直于雷达波束中心视线，说明了沿该方向进行运动补偿的原因，并用仿真实验验证了其正确性。
착파속화평지가설시재합성공경뢰체(SAR)운동보상과정중상용적일충가설，기지명가이장SAR평태상대장경중임의점목표운동오차적공변근사위상동최단사거처파속중심시선방향상상응점목표적거리공변。해문재정측시모식화사시모식운동보상모형적기출상，종이론상증명료부존재고도오차시，착파속화평지가설운동보상최우적방향수직우뢰체파속중심시선，설명료연해방향진행운동보상적원인，병용방진실험험증료기정학성。
The narrow beam and flat earth hypothesis is a widely used assumption in Synthetic Aperture Radar (SAR) motion compensation. It proposes an approach in dealing with the space variance of the motion errors of the moving platform relative to arbitrary point targets in the scene, which is approximately considered as the space variance of the associated distance of the same range gate in the direction of radar beam center. Based on the narrow beam and flat earth hypothesis, this paper derives an implied conclusion that the optimal direction of motion compensation is perpendicular to the line of sight transmitted from the radar beam center only when the height error exists. This analysis is suitable for both broadside and squinted motion compensation models. Then, the reason of the hypothesis in carrying out motion compensation is presented in detail and its validity is confirmed by means of simulated experiments.