高空平台位置不稳定性对平台间PPM调制光链路性能的影响

在建立高空平台位置不稳定性模型的基础上，推导PPM调制的光链路误符号率，分析平台位置不稳定性的三种运动方式对平台间误符号率的影响。仿真结果表明:平台转动角度对于光链路的影响最大；平台间距离的变化对于链路的影响最小。并且增加发射功率能够在一定程度上缓解平台位置不稳定性对光链路的影响；较宽的光束发散角对于HAP的不稳定性具有很好的适应性。在仿真条件下，当发散角大于20 rad时，误符号率的变化不是很明显。

Effect of high altitude platforms position instability on performance of PPM on inter-platforms optical links

Based on the model of high altitude platforms position instability, the symbol error probability of PPM on inter-platforms optical links was derived. Based on the symbol error probability, the effect of three moving modes due to high altitude platforms position instability on the performance of inter-platforms was analyzed. The simulation results show that platforms rotation has the greatest influence on inter-platforms optical links, and the changing of inter-platforms distance has the lowest influence on inter-platforms optical links. A wide optical beam waist has better adaptability in platform instability. But when beam waist is more than 20 rad, the improvement of system performance is insignificant.