针对可变增益中继策略，推导高空平台多跳光链路中断概率的下限表达式，分析大气湍流、跟瞄误差以及中继节点位置对平台间多跳光链路性能的影响。仿真结果表明，高空平台特有的大气湍流特性对于平台光链路性能的影响较小，而跟瞄误差对链路的影响很大；中继节点位置对多跳光链路的影响，与跟瞄误差相关。跟瞄误差越大，中继节点位置对于光链路的影响越大；通过增加平均每跳信噪比能够有效降低中继平台位置对链路的影响的同时，还能改善链路性能。以跟瞄误差为20 m，2次中继为例，平均每跳信噪比增加1 dB，链路中断概率降低约2.2 dB。

Based on variable gain relays, the expression of outage probability lower bound for high altitude platform multi-hop optical communication is given. The effect of the factors, including atmospheric turbulence, tracking error and relay node position, on the performance of multi-hop optical links is analyzed. The simulation results show that the influence of atmospheric turbulence on optical links is lower than pointing error. The influence of relay node position on multi-hop optical links is related with tracking error. The bigger tracking error is, the stronger is the dependence of the position of relay node on optical links. The influence of relay node position on inter-high altitude platform (HAP) optical link will worsen and the performance of multi-hop optical links can be improved by the improvement of signal noise ration (SNR). Taking relay number of 2 and tracking error of 20 m as an example, outage probability of links reduces approximately by 2.2 dB while the average SNR per hop increases by 1 dB.