摘要 : The gain of advanced optical communication systems is reduced by the noise of optical source. Coherent optical communication systems are in particular very sensitive to the noise transmitter and local laser. Optical space communic... 展开 The gain of advanced optical communication systems is reduced by the noise of optical source. Coherent optical communication systems are in particular very sensitive to the noise transmitter and local laser. Optical space communications is on the verge of being reality. The paper involves the introduction into laser satellite communication system. The paper includes briefly analysis, optimization, design and system level development of signal transferring between satellites. Research opportunities in this area include development of laser beam acquisition, tracking and pointing techniques and algorithms, development of computer aided analysis link budget for the free space channel, systems engineering (analysis and design) of optical transmission development of high efficiency flight qualifiable solid-state lasers, fast fine-pointing mirrors high update-rate acquisition and tracking cameras and very low-noise high-quantum efficiency receiver. It is focused on the noises' limits of the optical communication system. The paper solves the problems with noises' limits by various ways. There are mentioned the optical energy output on an aperture's spread of optical detector and incoherent detection of optical carrier wave. 收起