基于空域调制不稳定性的海洋水下目标高分辨光学成像技术研究

针对水下激光成像过程中散射引起的背景噪声难以消除的国际难题，特别是图像信号被同频散射噪声完全湮没无法用传统水下成像技术识别的情况，提出基于空域调制不稳定性的图像复原重构技术来提高水下目标成像分辨率和对比度。首先，理论构建光学图像水下传输理论模型，探究图像退化机理；其次，从理论上系统地研究非相干空域调制不稳定性的物理机理，并建立应用空域调制不稳定性效应实现浑浊水下强散射噪声湮没的弱光图像信号重构的理论模型，分析海洋水下环境中各种相关参数的影响，得到输出图像质量最佳存在条件。最后，从实验上研究水下强散射噪声条件下基于空域调制不稳定性的高分辨成像技术，通过优化系统参数实现具有较高分辨率和对比度的图像输出结果。本项目的研究有望为水下目标识别、跟踪、海洋勘测、搜索救援等领域提供有效的技术支撑，并促进相关领域的快速发展。

For the international difficult problem that the background noise induced by scattering is much more difficult to remove in the underwater laser imaging process, especially for the case that the image signal is completely hidden by scattering noise and cannot be identified by the conventional underwater imaging technology, we propose the reconstruction technology based on spatial modulation instability to enhance the image resolution and the contrast of the underwater target. Firstly, the theoretical model of underwater optical image transmission should be built to explore the mechanism of image degradation. Secondly, the physical mechanism of the incoherent spatial modulation instability should be systematically investigated in theory, and the theoretical model of using spatial modulation instability effect to reconstruct the weak image signal drowned by the strong scattering noise in the turbid water should be built. The optimum existing condition for the output image quality should be obtained by analyzing the correlative parameters of the underwater environment of the ocean. Finally, the underwater high-resolution imaging technology based on spatial modulation instability for the strong scattering noise will be investigated experimentally. The output image with high resolution and high image contrast will be obtained for the optimization of system parameters. The study of this project will provide an effective technology support for the areas of underwater target identification, track, ocean exploration, search and rescue, and contribute to the rapid development of the related fields.