The most typical weather restriction of Free-space Optical Communications System is the fog; the fog attenuation of laser is a main factor that affects the performance of the lasers communication.

雾是制约无线光通信系统的最典型气象条件，它对激光的衰减效应是影响光通信性能的主要因素。

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So Starkweather fired a laser through the air between the two buildings, an improvised communications system that meant that, if you were driving down the Foothill Expressway on a foggy night and happened to look up, you might see a mysterious red beam streaking across the sky.

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