Design Of The Large-aperture Splicing Antenna With Multi-curvature Spherical Sub-mirrors

Because optical communication has the advantages of large communication capacity and high transmission speed,it has great potential for development.Countries have invested a lot of energy in this field to conduct in-depth research,and China has also put forward new requirements for the development of optical communication.With the development of satellite optical communication and astronomical telescopes,and the improvement of people's requirements for communication and astronomical telescopes,the aperture of the optical antenna needs to be increased.However,as the aperture increases,the manufacturing,and processing difficulty of the optical antenna will be greatly increased,thereby increasing the cost.Splicing antennas are widely used because they can effectively reduce the manufacturing cost of optical antennas.However,the focusing effect of the existing splicing antenna is not good enough,and the optical performance needs to be improved.Therefore,designing a large-aperture splicing antenna with excellent performance is of great significance to the development of space optical communication.(1)In the Thesis,the multi-curvature splicing antenna(MCSA)is designed.To improve the optical performance of large-aperture splicing antennas,the Thesis optimizes the structure of the Cassegrain splicing antenna system with an aperture of 10 m.Based on the single-curvature splicing antenna(SCSA)composed of the same spherical sub-mirrors,the curvature of the parabolic primary mirror is fully considered.According to the changing trend,the spherical sub-mirror with proper curvature is selected as the sub-mirror unit of the splicing primary mirror,so that the splicing primary mirror is more similar to the ideal parabolic primary mirror,and then the best structure of the splicing antenna is selected through simulation and comparison.Finally designed a large-aperture splicing antenna composed of three layers of spherical sub-mirrors with different curvatures.(2)The Thesis analyzes and compares the performance difference between the MCSA and the SCSA.Through simulation,the transmission efficiency of the MCSA is82.92%,and the spot radius of its receiving surface is about 0.0109724 m.Compared with the SCSA with the same structural parameters,the spot size is reduced by 45.74%,and the focusing performance is significantly improved.(3)In the Thesis,the effects of the defocusing of the secondary mirror and the inclination of the incident light on the performance of the MCSA are analyzed.When the antenna system is out of focus and the incident light is inclined,the spot size of the receiving surface of the antenna system increases,the focusing performance decreases,and the transmission efficiency decreases.The Thesis also discusses the effect on the transmission efficiency of the antenna system when the number of layers of the splicing primary mirrors is changed.The research in this thesis provides a new idea for the design and optimization of large-aperture splicing antennas.