The global beam still adopts circular beam and regional communication, and most satellite communications adopt double-grid, orthogonal, single-feed and reflector antenna design. This antenna technology is not only used in most communication satellites; At the same time, it has also been mastered by the major satellite antenna manufacturers in the world, and the multi-beam shaped large antenna developed to support personal mobile communication has begun to be used. The main satellite antennas are as follows. The satellite antenna was developed by Hughes. The physical size of the antenna is 12.25m× 16m, the projection diameter is 12m, and there are 128 feeds, which are integrated with transmission and reception. The wireless device is like a double ring supported by a plurality of support rods, the upper ring has a transparent paraboloid support surface, the lower ring has a transparent paraboloid reflector, and the two paraboloids are tensioned by a plurality of strings. The unfolding and folding are simple and reliable, and the nodes of each support rod are connected and controlled by gears.
Wireless design has the following characteristics:
A pair of integrated transmitting and receiving satellite antennas. For any spot beam, the transmitting beam and the receiving beam will completely overlap (and there is no need for a second antenna, which greatly reduces the weight of the antenna subsystem.
Novel structural design, to achieve the purpose of miniaturization, simple and reliable deployment in the folded state.
The reflecting surface adopts a metal ring frequency selective surface plated on the dielectric film, which only resonates with the working frequency and reflects the rest, eliminating the contact between metal and metal and minimizing passive intermodulation.
The dielectric film is made of indium oxide, an incomplete insulator material, and its resistivity is about10 (power 8) ω, which not only ensures the complete unloading of static electricity, but also keeps the penetration of electromagnetic waves unaffected.
The perfect combination of 128 feed and on-board digital signal processor effectively ensures the requirements of spot beam in the coverage area. Using offset feed technology, every 8 or 20 or even more feeds form a beam, and the total number can form 200-300 point beams.
Multi-point beam with beam isolation of14db; The frequency reuse times (beam number /7) are greatly improved, and the satellite frequency and frequency band are greatly saved.
The design of spot beam ensures the high gain of antenna and effectively supports the demand of personal communication. The satellite antenna was developed by Harris Company in Orlando, USA, with a history of 100 years. Harris' antenna design adopts the traditional deployable truss antenna. The company has 20 years of research and development experience in large deployable antennas, including antennas in L, S, X and Ku bands, such as the 4.8-meter satellite antenna of TDRSS in the United States, which has been verified by flight and has strong strength and credibility.
ASES satellite adopts two deployable truss antennas of 12m, which are used for transmitting and receiving respectively. The antenna completely inherits the characteristics of the original antenna in structure and deployment driving mechanism, and has higher precision and reliability. The deployable truss structure with a diameter of 4.8 meters is wireless, with a total weight of 52 pounds;
The reflector consists of 18 graphite epoxy truss, reflecting surface, central control mechanism and motor-driven deployment system.
The central support member consists of six graphite wing brackets, a timely epoxy shield, a front nest reflector and a top cone;
The feed component includes sidelobe tracking and five KU-band feeds. 4.8m diameter deployable truss antenna with total weight of 76 lbs.
18 rigid reinforced carbon fiber epoxy resin truss;
Support feeder with adjustable beryllium support rod system
Molybdenum-plated mesh parabolic reflector;
Seglin reflector and spire reflector.