大气湍流影响星地相干激光通信的数值仿真

由于解析法在研究相干光通信的相位补偿等问题中存在困难，采用多层相位屏分步传输的数值仿真方法研究大气湍流对星地相干光通信下行传输的影响。首先建立了卫星地面之间的大气湍流中激光传输的仿真模型，可以实现不同天顶角和不同湍流条件下的光传输仿真计算。然后用其进行地球同步轨道(GEO)卫星下行光通信的数值仿真分析，并通过与理论值的对比来检验算法的可靠性。最后结合二进制相移键控(binary phase shift keying, BPSK)相干激光通信系统的误码率（bit error rate， BER）模型，计算分析了下行激光通信信号的衰落系数和BER。

Numerical Simulation of Influence of Atmospheric Turbulence on Satellite-to-Ground Coherent Laser Communication

It is difficult to resolve the phase compensation problem in the coherent optical communications using theoretical analytical method. To solve the problem, the split-step beam propagation method is used to study the influence of the atmospheric turbulence on satellite-to-ground coherent optical communication. The simulation model of the laser propagation in the turbulence is established. And then the geostationary earth orbit(GEO) satellite-to-ground downlink laser propagation is simulated. The simulation results are in a good agreement with the theoretical results, which proves the validity of this method. At last, using this simulation method, the fading coefficient and bit error rate of binary phase shift keying (BPSK) coherent optical communication are calculated and analyzed.