Novel Structure Design Of Laser-Emitting Antenna System And Its Transmission Efficiency Analysis

The current quality of the communication is required to be greatly improved as the high speed development of modern technology. In order to solve the problem of insufficient communication capacity, space optical communication started to become a hot research area by virtue of its advantages in size, weight, speed, power, and bandwidth costs. However, the space optical communication research field is confronted with the problem that the optical antenna system has generally low optical transmission efficiency nowadays, it is of great importance to carry out deep research about the quality of space optical communication.This thesis is based on the reflective law in vector ’s form and the methods of optical system design. Three novel structures of laser emitting optical antenna syste m are proposed. Their transmission efficiency are analyzed further as well as the parameters in these optical systems. Finally, the transmission efficiency diversification of the antenna system in case of deviation to some degree are discussed, then the deviation range of antenna systems within Strehl standard is analyzed. The main contents are as follows:(1) The domestic and foreign development overview of the free space communication technology are described. The significance about the study is obvious and the difficulties, which deserve to be solved are generalized together.(2) The application of the semiconductor lasers in space optical communication system is briefly introduced. And the principles and characteristics of semiconductor lasers are described. It is the appropriate collimation technology that need to be involved for the divergence of the semiconductor laser light source. Then the optical antenna structure classification is proposed, as well as the design requirements of the optical antenna finally.(3) The implementation of the optical system design and related software are given.Three novel structures of the laser emitting antenna system are proposed according the phenomenon that the obstruction of the secondary mirror in traditional Cassegrain optical antenna leads to low transmission efficiency. They are elliptical structure of the optical antenna system, two elliptical secondary mirror Cassegrain optical antenna systems and additional hyperbolic primary mirror Cassegrain optical(4) antenna system. Brief introduction of their components and the corresponding effect analysis is listed.(5) The parameters analysis and calculation of the three structures of optical antenna system are carried out. Then the transmission efficiency changes are obtained in the circumstance of given axial deviation in the antenna systems. The maximum deviation of antenna systems within Strehl standard are discussed.