相位编码合成孔径激光雷达关键技术研究

发布时间：2018-08-16 13:28

【摘要】：合成孔径激光雷达是一项新兴技术,其在距离向和方位向的分辨率均与作用距离无关,在遥感领域具有非常大的潜力。现阶段的实验研究均采用线性调频方式,调频速率和线性度均限制了其应用于快速运动平台。对于相位编码合成孔径激光雷达的研究较少,存在很多技术难点需要进一步突破。论文围绕基于相位编码调制合成孔径激光雷达的关键技术展开了研究,其主要研究内容为:1)就国内外合成孔径激光雷达发展现状进行了介绍,简要介绍了合成孔径原理,同时对光电子技术发展情况进行了梳理;2)对合成孔径激光雷达典型技术手段原理进行了阐述,分析了线性调频技术特性及其局限性,提出相位编码调制方式,并在理论实验上进行了验证;3)分析了相位编码合成孔径激光雷达系统参数,对其中关键技术进行梳理,进行了关键组部件技术攻关,;4)针对不同目标运动形式进行了实验验证,包括平动目标和非合作目标等复杂运动形式,分别对两种运动形式下成像特点进行了总结归纳,提供了实验参考;5)针对不同目标表面的反射特性进行了研究,就其中的退相干特性进行了实验研究,同时考虑目标反射回波缺失和低信噪比等问题,提出压缩感知在相位编码合成孔径激光雷达方位向应用的处理流程。本论文的创新点主要体现在以下几个方面:1.首次系统性地分析相位编码合成孔径激光雷达中各项关键技术,详细分析了系统中重要指标;对其中的宽带信号调制、高重频光开关、自由空间正交解调、高速光电转换等关键组部件进行了技术攻关,为系统实现提供了硬件支持。2.首次完整地分析了相位编码合成孔径激光雷达针对不同运动形式和不同目标特性的成像能力,为相位编码合成孔径激光雷达不同应用场合提供了参考;针对应用场合下,回波缺失和低信噪比等情况,提出了压缩感知与相位编码合成孔径激光雷达方位向处理结合的成像算法,有效增强了系统的实用性。
[Abstract]:Synthetic Aperture Lidar (SAR) is a new technology whose resolution in range direction and azimuth direction is independent of range and has great potential in remote sensing field. At present, the experimental research adopts the linear frequency modulation mode, which limits its application to the fast moving platform. There are few researches on phase coded synthetic aperture lidar, and many technical difficulties need further breakthrough. In this paper, the key technology of phase-coded modulation synthetic aperture lidar (SAR) is studied. The main research content is: (1) the development status of synthetic Aperture Lidar at home and abroad is introduced, and the principle of synthetic Aperture is briefly introduced. At the same time, the development of photoelectron technology is reviewed. The principle of typical synthetic aperture lidar (SAR) technology is expounded, the characteristics and limitations of LFM technology are analyzed, and the phase-coded modulation method is proposed. The system parameters of phase-coded synthetic aperture lidar are analyzed, the key technologies are combed, and the key component technology is studied. In this paper, the imaging characteristics of the two kinds of moving objects are summarized and summarized respectively, which includes the translational target and the non-cooperative target. 5) the reflection characteristics of different target surfaces are studied. In this paper, the decoherence characteristics are studied experimentally, and the problems of missing reflection echo and low signal-to-noise ratio (SNR) are considered, and the processing flow of phase coded SAR azimuth direction is proposed. The innovation of this paper is mainly reflected in the following aspects: 1. The key technologies of phase-coded synthetic aperture lidar are analyzed systematically for the first time, and the important indexes in the system are analyzed in detail, including broadband signal modulation, high repetition frequency optical switch, free space quadrature demodulation, and so on. The key components, such as high speed photoelectric conversion, are used to solve the technical problems, which provide hardware support for the system. 2. 2. For the first time, the imaging ability of phase-coded synthetic aperture lidar for different moving forms and different target characteristics is analyzed, which provides a reference for different applications of phase-coded synthetic aperture lidar. In the case of missing echo and low signal-to-noise ratio (SNR), an imaging algorithm combining compression sensing and phase coded SAR azimuth processing is proposed, which effectively enhances the practicability of the system.
【学位授予单位】：中国科学院研究生院(上海技术物理研究所)
【学位级别】：博士
【学位授予年份】：2016
【分类号】：TN958.98

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