The way of fully optical acquisition for the near earth surface laser communication

Space laser communication possess lots of advantages, such as speed, security, and the strong ability of resisting electromagnetic interference, etc, which recently receiving more and more attentions. But the acquisition process, it almost uses electric methods and the ability of resisting electromagnetic interference is poor. How to realize safe and reliable beam acquisition on the near earth surface with complicated electromagnetic environment is one of the factors that restrict the application of the laser communication. This article, in view of the above requirements, puts forward an elliptical beacon light realizing fully optical acquisition method, and establishes a mathematic model of scan acquisition and then discusses the parameters of beam spot shape. Finally, we analyze the relationship between acquisition time and beam spot shape, and the result shows that, this method can realize the beacon light of capture, and provides feasible technology solutions for laser communications under the complicated electromagnetic environment through the reasonable design beam divergence angle and scanning speed.