The Research And Design Of Space Optical Communication System

Nowadays information industry has become one of the most driving high technique grew-up points and the supports of economic society. The technology of laser communication is bringing the world into the information times with incogitability speed. As an important embranchment of laser communication, space optical communication can be applied widely such as the communication between satellites, wireless interconnection, wireless broadband access, emergency communication. Along with maturity of the technologies including exceedingly stable laser diode, new type of controller of light beam, high sensitivity and high speed receiver and advanced communication device, space optical communication has become one of the main developing directions of laser communication of next generation.In this thesis,WDM technology based on space optical communication is entirely introduced and 4 X 2.5Gb/s 4.4km WDM atmospheric laser communication system and 40Gb/s 4.4km DWDM atmospheric laser communication system are analyzed in detail. The structure of space optical communication system is deep studied from the aspects including laser transmission, signal receive and optical system. Adopting MAX4106, MAX435, MAX436 and MAX9691 chips of MAXIM company designs photoelectric receive circuit. Furthermore the tolerable limit of system power is calculated and the factors that affect the communication distance are analyzed. Aiming at the difficulties of laser transmission in atmosphere that space optical communication is facing and according to diffraction theory, the distribution of light intensity, which is affected by the fluctuation of refractive index field of the atmospheric turbulence, is deduced and simulated by MATLAB. finally, the experiment of double wavelenghs wireless optical communication is carried through. The results show that applying WDM technology to space optical communication is completely feasible and can enlarge communication capacity consumedly.