抑制大气湍流影响的新型光场频谱采样阵列及高分辨计算成像机制研究

The ground-based laser field imaging telescope is a new type of high-resolution computational imaging technology by lengthening the interference baseline between laser beams to improve the resolution of space targets. Atmospheric turbulence flicker is the main technical bottleneck and difficulty that restricts the image quality enhancement. This project research the problem of degradation of image quality caused by atmospheric turbulent scintillation. In order to effectively suppress enthalpy and enhance image quality, a new theory for eliminating turbulence disturbances from the perspective of a laser field spectrum sampling array is studied. The proposed research includes: 1) The influencing relation model between turbulence disturbance factor and the image quality degradation will be studied; 2) A novel spectrum sampling imaging method and novel laser emission array configuration that can suppress the flicker degrading effect of turbulent light intensity will be researched. 3) It studys high-resolution computational imaging algorithms based on all-phase theory. 4) It builds laser field imaging experiment system with different configurations of laser emission arrays. It analyzes and compares the advantages and disadvantages of various imaging array models and turbulence suppression effects. 5) It explores a new imaging theory that can effectively suppress the atmospheric turbulent scintillation. The turbulence suppression theory method provides important technical support for further improving the high-resolution image quality of the laser field. And the research is an important supplement to the existing high-resolution imaging theory. This novel imaging technique has broad application prospects in the field of small target detection, remote sensing and imaging and so on.

地基激光场望远镜通过拉长激光束间的干涉基线长度，提高对空间目标的分辨率，是一种新型高分辨计算成像技术，该技术尚未工程化，相关理论有待完善，目前大气湍流闪烁是制约其像质提升的一大技术瓶颈。本申请针对湍流闪烁引起的像质退化问题，从激光场发射采样阵列视角，研究可抑制湍流的激光场频谱采样阵列和高分辨计算成像机制。研究内容包括：1）研究构建湍流光强扰动因子对激光回波场和像质影响传函；2）研究可抑制湍流闪烁的新型激光发射阵列构型和新型频谱采样方法，消除湍流光强扰动因子对像质影响。3）研究基于全相位理论的高分辨计算成像机制和成像去噪算法。4）构建不同阵列构型光场成像实验平台，分析比较不同阵列湍流抑制效果，优化发射阵列。探索建立简洁高效，可抑制湍流效应的新型激光采样阵列和新成像机制，为大幅提升像质提供重要理论支撑，是现有高分计算成像理论的重要补充和发展，该技术可应用在高分成像领域，具有广阔应用前景。

不同于常规光学成像技术，地基激光光场成像望远镜是一种新型计算成像技术，大气湍流闪烁是制约其像质提升的一大技术瓶颈。本项目针对大气湍流光强闪烁如何影响激光光场重构图像像质及如何抑制消除大气湍流引起的像质退化两个科学问题开展研究。揭示了大气湍流光强闪烁对光场成像像质影响机理，并依据该影响机理提出了基于新型光场频谱采样阵列的大气湍流扰动抑制新理论方法，主要研究进展如下：1）建立了大气湍流光强闪烁对光场成像像质影响传函理论模型，揭示了大气湍流光强闪烁对像质影响机理，给出并证实了大气湍流光强闪烁主要通过光强扰动因子影响光场回波信号频谱分量，并进而引起光场成像像质退化的结论；2）提出了可抑制湍流光强闪烁的半米字型频谱采样成像新机制和新型激光发射阵列构型，抑制了湍流闪烁引起的像质退化效应，有效提升了成像像质；3）提出了基于激光光场阵列光强系数比求解的湍流扰动抑制理论方法，提升了光场成像质量；4）提出了基于同态滤波和信号稀疏理论的光场成像系统乘性散斑噪声和加性噪声的复合去噪理论模型，有效提高了系统成像像质；5）构建了基于定量化数值仿真的大气湍流光强闪烁仿真实验平台，定量化研究了大气湍流光强闪烁效应引起的像质退化机理；6）构建了光场成像实验平台，完成了大气湍流测量与湍流扰动抑制理论方法和关键技术的有效性验证。本项目研究成果为提升光场高分辨成像像质提供了新的理论方法和重要技术支撑，该湍流扰动抑制理论和技术方法可应用在地对空远程目标探测成像、高分辨遥感成像等领域，具有广阔应用前景。