Research On Some Key Technologies Of Space Optical Communication

Space optical communication is a kind of communication fashion best possessed foreground. It includes ground atmosphere optical communication and optical satellite-ground communication and optical intersatellite communication. At present research mainly concentrate on theoretics analyse, method argumentation and basic component. There is a distance apart from examination in satellite. Hence it is essential that the paper explore and research on space optical communication key technology.Based on briefly presented space optical communication conception, internal and overseas developmental actuality and trend, key technology, it process to profoundly research on high performance channel coding technology, high power light source, exact beam of light collimation technology, exact, dependable, high gain receive and transmit antenna and high sensitive degree, jamming-rejection optical receive technology in key technology.Based on analysis on coherent optical communication system structure, principle and applied situation, intersatellite coherent optical communication system based on Turbo code is investigated. Based on analysis on noises of intersatellite optical communication, characteristic curve is presented with simulation. Compared with BPSK modulation coherent optical communication system and PPM modulation direct detection optical communication system and uncoded system in virtue of system BER upper limit, Turbo code technology improves jamming-rejection capability of system, effectively save transmission optical power in coherent optical communication system.A kind of new exact beam of light collimation technology is presented, namely used polymer fiber taper to collimate. This is an important part among research content. Analysis on beam of light collimation principle used polymer fiber taper, a kind of polymer 3 level fiber taper applied collimation system with fiber plano-convex located front is investigated. Combined with analysis on beam of light transmission characteristic, polymer fiber taper system parameter are designed and angle after collimation can be achieved with simulation. All kinds of capability of polymer fiber taper in collimation are particular discussed. The controllable polymer fiber taper is investigated, namely piezoelectric ceramic ring used voltage control change diameter of fiber taper to less adjust angle. Polymer fiber taper not only possess excellent collimation capability, beam of light quality but also enhance couple efficiency of laser to fiber taper used fiber plano-convex located front. Such new collimation require to research deeply through experimentation.Based on optical heterodyne frequency response measurement principle, a kind of photodetector frequency characteristic measurement system used dual phase-shifted fiber gratings is investigated. Analysis on phase-shifted fiber gratings principle, metrical condition is discussed and 15GHz band width photodetetor frequency response measurement result is achieved and insulted between light source and phohtdetector optical component frequency response can be measure. The measurement method can guarantee metrical precision, possess some characteristic such as easy realization, cheap component.In order to achieve high capability receive antenna, base on analysis on optical antenna important parameter used in optical communication, satellite coherent optical communication optical antenna array characteristic is investigated. Fiber distributed serial antenna array is advanced and analyzed. The antenna array possess some superiority, enlarge equivalent caliber and debase point angle require to intersatellite optical communication. Fiber distributed serial array sub antenna principle constructed by combine prism with fiber is investigated. Analysis on characteristic index ground for experiment of fiber distributed serial antenna array.