共查询到18条相似文献,搜索用时 265 毫秒
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"停-走"模式是目前脉冲SAR信号处理和理论分析的基础.FM-CW SAR由于其大的脉冲重复周期和100%的信号占空比,使接收回波信号相对发射信号的畸变更加严重,因此,检验与该脉冲有关的畸变的影响是十分重要的.本文分析了FM.CW SAR"停.走"模式成立的条件;在"停一走"模式失效的情况下,提出一种改进的基于波前重构理论的FM·CW SAR的距离堆栈成像算法,算法中考虑了FM-CW SAR回波信号扫频周期内的畸变校正问题,精确的实现了二维成像.通过理论推导及仿真实验,均验证了算法的正确性与可行性. 相似文献
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王海鹏 《电气电子教学学报》2013,(5):97-99
为使大学本科生在学习“遥感原理与技术”时理论联系实际,笔者在该课程教学过程中,结合所在实验室所搭建的调频-连续波(FM-CW)雷达系统,详细讲述系统硬件构成、工作原理与信号处理算法;并以本系统为例,讲解合成孔径雷达(SAR)成像技术.教学实践结果表明,该方法能有效提高学生对SAR成像原理与方法的认识. 相似文献
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机载下视稀疏阵列三维SAR系统及成像 总被引:2,自引:0,他引:2
主要介绍了阵列三维SAR成像系统的基本理论,讨论一种双侧放置发射阵元的单激励稀疏阵列三维SAR成像系统;利用相位中心近似原理对天线进行优化,推导了阵列三维SAR系统的模糊函数,详细分析了稀疏阵列三维SAR分辨率特性;最后,讨论了三维SAR系统的RD成像算法,并进行了仿真成像. 相似文献
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"停-走"模式是目前脉冲SAR信号处理和理论分析的基础,FM-CW SAR由于其大的脉冲重复周期和100%的占空比,恶化了接收脉冲的畸变。文中分析了当天线斜视角增大时,导致传统距离-多普勒算法性能下降的主要误差来源,对FM-CW SAR的信号处理问题进行深入研究,提出了改进的适合斜视FM-CW SAR大扫频周期的距离-多普勒算法。通过理论推导及仿真实验,验证了改进模型和算法的可行性与正确性。 相似文献
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无人机SAR/MTI侦察技术中若干问题的探讨 总被引:1,自引:1,他引:0
本文介绍了国外无人机SAR/MTI雷达研究现状和发展方向,列举了X、Ka,Ku三种频段SAR/MTI雷达主要技术指标,重点从工程实现的角度对SAR/MTI雷达技术中若干问题进行了探讨,包括无人机、SAR的成像模式和MTI兼容技术、频段选择、SAR成像实时数据的传输方式、惯导系统、最后讨论了成像算法。 相似文献
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Yamaguchi Y. Mitsumoto M. Sengoku M. Abe T. 《Geoscience and Remote Sensing, IEEE Transactions on》1994,32(1):11-18
Presents the principle of synthetic aperture frequency modulated continuous wave (FM-CW) radar and demonstrates the detection results of several objects buried in natural snowpack using the radar system. First, the synthetic aperture technique is explained with emphasis placed on showing that the Fourier transformed beat signal obtained by the FM-CW radar is equivalent to one kind of Fresnel hologram, which leads the authors to use the SAR technique. Then a radar system operative in the microwave L-band is explored to detect objects buried in natural snowpack. Several detection results are presented demonstrating the potential capability of high resolution imaging in the azimuth direction, comparing with real aperture images 相似文献
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Yamaguchi Y. Nishikawa T. Sengoku M. Boerner W.-M. 《Geoscience and Remote Sensing, IEEE Transactions on》1995,33(2):421-427
Applies the principle of radar polarimetry to a synthetic aperture frequency-modulated continuous wave (FM-CW) radar and presents results based on two-dimensional (2D) full polarimetric imaging. It is shown that the polarimetric target reflection coefficients obtained by the synthetic aperture FM-CW radar are elements of a Sinclair scattering matrix, although the coefficients are derived from a wide band signal. Using the scattering matrix optimization procedure, a 2D polarimetric imaging experiment (including Co-Pol maximum, minimum, span, and phase imaging) of an orthogonally placed linear target set was successfully carried out in the laboratory. This result demonstrates the validity of N-band (8.2-9.2 GHz) FM-CW radar polarimetry, and it presents a demonstration of a full polarimetric 2D FM-CW imaging radar system 相似文献
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调频连续波(FMCW)SAR是一种新近提出的成像雷达体制,它结合调频连续波与合成孔径成像技术,具有体积小、重量轻、成本低、功耗低、分辨率高、截获概率低等一系列优点。文章归纳了目前FMCWSAR的几种应用背景及其主要参数,并根据FMCW SAR的发展概况,讨论了其进一步的发展趋势。 相似文献
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This paper presents a system model and inversion for airborne synthetic aperture acoustic (SAA) imaging. The system model accurately represents the intercation of the acoustic source and the target region at near range values. Moreover, the model incorporates the fact that the relative speed of the vehicle's (transmitter/receiver) with respect to the target region is comparable to the acoustic wave propagation speed. The inversion utilizes the principle of spectral decomposition of spherical phase functions to develop a wavefront reconstruction method from SAA data. Processing issues and selection of appropriate acoustic FM-CW sources are discussed. Results are provided that exhibit the superior accuracy of the proposed SAA system model and inversion over their synthetic aperture radar (SAR) counterpart in which the vehicle's speed is assumed to be much smaller than the wave propagation speed 相似文献
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线性调频连续波合成孔径雷达(LFMCW SAR)是一种新近提出来的成像雷达体制,它结合调频连续波与合成孔径成像技术,具有体积小、重量轻、成本低、分辨率高等一系列优点.然而,由于受系统的影响,调频信号的频率和时间并不完全满足线性关系.在详细分析了LFMCW的调频非线性对距离分辨率及FMCW SAR成像质量的影响之后,提出使用分段线性拟合的方法估计调频信号的非线性,并提出了非线性的校正方法,研究了存在非线性时的FMCW SAR成像算法,并给出了仿真结果,验证了该方法的有效性. 相似文献
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空载合成孔径雷达技术及展望 总被引:5,自引:1,他引:4
空载合成孔径雷达(SAR)是一种现代高分辨率侧视成象雷达,它应用合成孔径技术、脉冲压缩技术和数字信息处理技术,获得方位向和距离向的高分辨率。本文将对空载SAR的现状及发展趋势进行综述,并主要讨论SAR的有关技术,涉及星载SAR工作模式和体制,雷达数字图象的信息获取与成象处理等,最后,给出了SEASAT-A卫星SAR数字成象结果。 相似文献
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Presents experimental results of polarimetric detection of objects buried in a natural snowpack by a synthetic aperture FM-CW radar. First, the principle of polarimetric imaging in the Co- and Cross(X)-pol radar channels is outlined based on the scattering matrix and the characteristic polarization states for a specific target. Then, polarimetric measurements were carried out to detect objects buried in a natural snowpack 230 cm deep. The targets included two orthogonally placed metallic plates, an ice layer within the snowpack, and a human body. It is shown that the polarimetric FM-CW radar clearly enhances target signatures and that it serves to significantly improve detection in snowpack. Several polarimetric detection results are displayed, demonstrating the potential capability of characteristic polarization imaging and the usefulness of FM-CW radar 相似文献