论文标题
降低自适应光学滞后对快速移动源的光学和量子通信率的影响
Reducing The Impact Of Adaptive Optics Lag On Optical And Quantum Communications Rates From Rapidly Moving Sources
论文作者
论文摘要
光线穿过湍流气氛的波前会变形。这会导致自由空间光学通信的信号损失，因为光束在接收端散开和徘徊。频率和/或时间分级多重自适应光学（AO）技术已被用来连接这种波前变形。但是，如果信号光束相对于大气移动，则AO系统性能由于高颞动物星际作用而降低。在这里，我们通过添加一个先锋灯塔来解决此问题，该灯塔在空间延迟的空间延迟之间在空间分离的脉冲之间进行空间分离。更重要的是，我们的协议有效，无论信号光束强度如何，因此也适用于秘密量子通信。特别是，使用半经验的大气湍流计算，我们表明，对于低地轨道卫星到地面诱饵状态量子密钥分布，卫星在天顶角$ <30^\ circ $，我们的方法将关键利率提高至少$ 215 \％\％$ $ $，$ 40 \％\％\％$ $ 400 $ $ 400 $ $ $ 〜km和$ 800 $ 800 km〜km〜km〜km〜km〜km〜km〜km〜km〜最后，我们提出对现有波长多路复用系统的修改，作为解决此问题的有效替代解决方案。
Wavefront of light passing through turbulent atmosphere gets distorted. This causes signal loss in free-space optical communication as the light beam spreads and wanders at the receiving end. Frequency and/or time division multiplexing adaptive optics (AO) techniques have been used to conjugate this kind of wavefront distortion. However, if the signal beam moves relative to the atmosphere, the AO system performance degrades due to high temporal anisoplanatism. Here we solve this problem by adding a pioneer beacon that is spatially separated from the signal beam with time delay between spatially separated pulses. More importantly, our protocol works irrespective of the signal beam intensity and hence is also applicable to secret quantum communication. In particular, using semi-empirical atmospheric turbulence calculation, we show that for low earth orbit satellite-to-ground decoy state quantum key distribution with the satellite at zenith angle $< 30^\circ$, our method increases the key rate by at least $215\%$ and $40\%$ for satellite altitude $400$~km and $800$~km, respectively. Finally, we propose a modification of existing wavelength division multiplexing systems as an effective alternative solution to this problem.
