海洋湍流对激光传输特性和光学成像的影响

项目名称： 海洋湍流对激光传输特性和光学成像的影响

项目编号： No.61475105

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 无线电电子学、电信技术

项目作者： 季小玲

作者单位： 四川师范大学

项目金额： 72万元

中文摘要： 随着水下光通信、成像、传感和激光雷达等应用的兴起，水下环境对激光传输和成像提出了新的挑战。迄今为止，海洋湍流对激光传输特性和光学成像影响的研究涉及甚少。与大气湍流不同，海洋湍流是由温度和盐度变化引起水折射率起伏而造成的，其折射率起伏空间功率谱具有复杂的双峰值结构。双峰值结构的海洋湍流功率谱能够比Kolmogorov功率谱更精确地预测光在海洋湍流中的传输行为。本项目拟研究内容：研究海洋湍流中的光波结构函数和光波空间相干长度（海洋光学中的关键科学问题）；修正水下光学成像模型，研究海洋湍流对光学成像质量和望远镜分辨本领的影响；利用室内湍流池模拟海洋湍流，并采用解析、数值模拟和实验相结合的研究方法，寻找减小海洋湍流和热晕对激光束质量影响的途径。本项目结果将提供海洋湍流中激光传输以及光学成像的研究模型、方法和数值模拟软件，揭示海洋光学中的新规律，为工作于水下湍流环境中的相关应用提供理论基础。

中文关键词： 海洋湍流；光波空间相干长度；光波结构函数；光学成像；激光传输特性

英文摘要： Since recently the interest in underwater communications, imaging, sensing and lidar appeared, the laser beam propagation and the optical imaging in underwater environments pose significant challenges. Until now, only a few studies have dealt with the influence of oceanic turbulence on the propagation property of laser beams and the optical imaging. Unlike in the case of atmospheric turbulence, the oceanic turbulence is caused by both temperature fluctuations and salinity fluctuations. The spatial power spectrum of the refractive index fluctuations of oceanic waters may have two-bump structure. The new power spectrum of oceanic waters allows for more accurate predictions of the light propagation behavior in the ocean than the Kolmogorov spectrm. In this project, we study the wave structure function and the spatial coherence length in oceanic turbulence, which is the one of the base and the key problems of oceanic optics. We modify the underwater imaging model, and study the influence of oceanic turbulence on the imaging and the resolution capability of telescopes. We simulate the oceanic turbulence in the laboratory water tank, and explore the ways to decrease the influence of oceanic turbulence and thermal blooming on the laser beam quality by using the analytical method, numerical calculation method and experimental method. The results obtained in this project will provide the analysis model, the calculation method and the numerical simulation software for the laser beam propagation and the optical imaging in oceanic turbulence, discover new results in oceanic optics, and provide theories for applications in oceanic turbulence.

英文关键词： oceanic turbulence;wave spatial coherence length;wave strture function;optical imaging;propagation property of laser beams