Spaceborne Laser Communication Optical Antenna Design And Mirror Thermal Deformation Finite Element Analysis

Space optical communication has much advantage such as much greater communi- cations capacity, high-bit-rate, high secrecy, high anti-electromagnetic disturbance, small size and low attenuation. It is a lively branch of communication. So each country attaches important attention to space optical communication, and achieves great progress. The Optical antennas system, which is a important component of the system of space optical communication, and it's performance will affects on the running of total system. Therefore, it is important to select and design the right optical antenna.Firstly, space optical communication is introduced briefly in paper, discuss the advantage, the application fields and research meanings, introduce the development situation, and the application foreground as well as development trend about the space optical communication are synoptically narrated. Then the main structure, integral parts, the key technologies, the factors and countermeasures of influencing the performance of space optical communication are discussed.Paper introduces the sorts and request for design of optical antennas, choosing the cassegrain antennas based on the characteristic of space optical communication. The structure and work principle of cassegrain antennas are discussed, as well as the relation of parameters each other. Participate in the design and test of the cassegrain antennas used in one subject.According to the characteristic of high vacuum thermal environment in low orbit,it builds the theoretical modeling of the thermal analysis of thermal distortion in optical reflector of antennas system. making use of the results reached by ANSYS software, it analyzes and compare the stress and distortion of reflector under the static temperature. it compute the parameter of deflexion caused by thermal distortion in orbit, deduce the general expression for spreading beam after thermal distortion of reflector and the center deflexion of facula received in CCD. With the method of fixing etc, it put forward the restrain measures adopted accordingly. Linking to the request of the research subject, it designs and tests the cassegrain optical antennas.