Cassegrain antenna system based on free-space laser communication

Antenna, which whether transmits or receives correct signal or not is our main care and our direction, is an important part in any communication systems. Because of the characteristics of laser different from radio, the antenna system of point-to-point laser communication system must be designed strictly. In this paper, we mainly study the optical antenna in the space communication. We describe the optical antenna's structure. The performances of optical antenna are first given in this paper.