AI 中文总结
研究低地球轨道卫星到地面低仰角光通信中自适应光学设计，以夏克 - 哈特曼波前传感器为例提出对闪烁鲁棒的设计方法，经模拟和误差预算讨论其可行性，可减小波前测量误差。
AI 中文摘要
为使低地球轨道卫星的光下行链路持续时间最大化，即便在低仰角时确保光信号耦合到地面终端的单模光纤也至关重要。自适应光学系统旨在校正大气湍流引起的波前变形，但在低仰角时，幅度波动（即闪烁）对这种校正构成挑战。本文以夏克 - 哈特曼波前传感器为例，提出一种设计对闪烁具有鲁棒性的波前传感器的方法。给出一种能处理子孔径间大动态强度范围的斜率估计器。接着展示了自适应光学系统的端到端模拟，以表明瞳孔平面更精细采样带来的波前测量误差减小。最后通过低地球轨道光下行链路情况下详细的自适应光学误差预算讨论了这种设计的可行性。
英文摘要
To maximize the duration of optical downlinks with Low-Earth Orbit satellites, it is crucial to ensure the coupling into the single mode fiber of the ground terminal even at low elevations. Adaptive optics systems are designed to correct the wavefront deformation induced by atmospheric turbulence. However, at low elevations, amplitude fluctuations (or scintillation) challenge this correction. Here we propose a methodology to design a wavefront sensor that is robust to scintillation, taking the Shack-Hartmann WFS as an example. We present a slope estimator able to handle the large dynamic intensity range between subapertures. We then present an end-to-end simulation of the AO system to show the decrease in wavefront measurement error brought by a finer sampling of the pupil plane. Finally, we discuss the feasibility of such design by means of a detailed AO error budget in the case of a LEO optical downlink.
Journal refSPIE LASE 2025, Jan 2025, San Francisco, United States. pp.1335519
