在入射光瞳面处针对星地激光链路中空间光至单模光纤耦合效率补偿特性进行了研究,依据星地下行链路特点,对星地下行链路光纤耦合效率模型进行分析。在此基础上,利用基于单模光纤后向传输模场为加权函数的加权孔径正交多项式,建立光纤耦合接收系统波前相位模式补偿理论模型,运用该理论模型,通过数值模拟对波前相位进行模式补偿,给出波前相位模式补偿下平均光纤耦合效率与接收孔径尺寸和相位补偿项数的变化关系,以及典型接收孔径下采取一定项数的波前相位补偿后光纤耦合效率概率分布,为基于光纤耦合接收方式的星地激光通信链路波前补偿系统设计提供一定理论参考。
Compensation characteristic of coupling efficiency in process of coupling space light into single-mode fiber was studied in the satellite-to-ground link. According to satellite-to-ground link feature, coupling efficiency model was analyzed. Wavefront phase modal compensation model using orthonormal polynomials on pupil weighted by the backpropagated fiber mode field was built. Based on this model, the relation between average fiber coupling efficiency and received aperture diameter or phase modal term compensated was obtained by numerical simulation. The probability distribution of coupling efficiency was given for typical received aperture by using different term modal compensation. The research work can offer a useful reference for compensation system design of satellite-to-ground optical communication based fiber coupling way.