空间光通信中光源相干参数对接收光强影响研究

Research on the effect of Source Coherent Parameter on the Incident Optical Intensity in Space Laser Communication Link

空间光通信中,光源空间相干度变化会对光信号的传输造成影响,使接收端处的入射光场发生变化。本文综合考虑了光源相干参数变化引起的平均接收光强及光强闪烁指数的变化,给出了基于部分相干光源的接收光强概率分布模型。仿真研究结果表明,光源相干参数增大对接收光强的影响近似于相同条件下大气湍流强度增强的结果。随着光源相干参数的增大,平均接收光强下降,接收光强的概率分布曲线向光强较小的一侧偏移,且随着偏移量的增加,接收光强会更加集中的分布在平均接收光强两侧,使得接收光强的概率峰值增大。空间光通信中,考虑光源空间相干度变化条件下,所获得的接收光强概率分布对接收系统的冗余设计具有一定的实用价值。

In space optical communication link,the incident optical intensity at the receiver aperture is affected by the source coherent parameter. In this paper,with full consideration of both the average optical intensity and scintillation,the statistical distribution model of the incident optical intensity with a partially coherent laser source is obtained. The simulation results manifest that the effect on the degradation of incident optical intensity with an increasing source coherent parameter is very similar to that with a stronger atmospheric turbulence. The average optical intensity and the scintillation will invariably degrade with increasing source coherent parameter. The hope of this paper is to improve the redundancy design of the laser communication receiver.