半导体激光云高仪收发系统关键技术研究与设计

发布时间：2018-01-10 03:24

本文关键词：半导体激光云高仪收发系统关键技术研究与设计　出处：《中国科学技术大学》2017年硕士论文　论文类型：学位论文

【摘要】：云是漂浮在空气中的水滴、冰晶汇聚的结果。它反映着空气中水汽的运动状态和稳定程度等,可以预示天气变化,与我们的日常生活休戚相关。云底高度是观测云的一个重要参数,准确测量云底高度,可以为掌握天气变化规律提供技术支持,为日常生活和生产活动提供行动指南,为交通运输以及飞机和航天器等起飞、着陆和飞行安全做保证等。为解决气象局与机场等对150m～7500m范围内云底高度信息精确、实时获取的需求,为此本文对半导体激光云高仪收发系统关键技术进行了研究与设计。首先,针对激光功率与后向散射信号的特点,设计了发射和接收分离的双光轴系统结构。然后,设计了长焦距单透镜与小孔光阑结合来完成半导体激光器光束扩束准直的发射系统,使出射光束发散角约为0.667mrad;设计了伽利略望远结构滤波和二次聚焦透镜来完成后向散射信号的接收系统,使接收视场角约为2.5mrad。并对设计的光学系统用Zemax软件进行仿真验证,仿真结果与设计结果基本相符,证明了设计系统的可行性。同时完成了发射系统与接收系统的机械结构设计。设计的系统避免了收发系统间的光干扰,同时降低了光学系统的复杂度,并分别提高了系统对近场与远场云层的探测能力。另外,对影响系统信噪比的关键因素光轴重叠因子进行了研究,并用matlab数值模拟方法模拟光轴偏移夹角对重叠因子的影响,同时设计了基于CCD成像调节非可见光系统光轴平行的调节方法,有效减小光轴间的偏移夹角确保了光轴平行度。最后实验测试结果表明,该方案可以有效配合采集与反演系统完成需求范围内云高的实时、准确测量。
[Abstract]:Cloud is the result of water droplets floating in the air, ice crystals converging. It reflects the movement and stability of water vapor in the air, and can predict the change of weather. Cloud base height is an important parameter for cloud observation. Accurate measurement of cloud bottom height can provide technical support for understanding the law of weather change. Provide operational guidance for daily life and production activities, and take off for transport and aircraft and spacecraft. Ensure landing and flight safety. In order to meet the needs of meteorological bureau and airport for accurate and real-time acquisition of cloud bottom height information within a range of 150mb 7500m. In this paper, the key technology of semiconductor laser hoist transceiver system is studied and designed. Firstly, the characteristics of laser power and backscattering signal are analyzed. The structure of the dual-axis system is designed. Then, the beam spread collimation system of semiconductor laser is designed by combining a single lens with long focal length and a small aperture. The divergence angle of the beam is about 0.667mrad. In order to complete the backscattering signal receiving system, the Galileo distant structure filter and the secondary focusing lens are designed. The received field of view angle is about 2.5mrad. and the designed optical system is simulated with Zemax software, and the simulation results are basically consistent with the design results. The feasibility of the design system is proved. At the same time, the mechanical structure design of the transmitting system and the receiving system is completed. The designed system avoids the optical interference between the transceiver system and reduces the complexity of the optical system. The detection ability of the system to near-field and far-field clouds is improved respectively. In addition, the key factors affecting the SNR of the system are studied, such as the overlap factor of optical axis. Matlab numerical simulation method is used to simulate the influence of the offset angle of optical axis on the overlap factor, and a parallel adjustment method based on CCD imaging is designed to adjust the optical axis of non-visible light system. Finally, the experimental results show that the proposed scheme can effectively cooperate with the acquisition and inversion system to achieve the real-time and accurate measurement of cloud height in the range of requirements.
【学位授予单位】：中国科学技术大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TH765.61;TN24

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