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산란대기하에서 광위성 통신 업링크의 양각에 따른 송신 안테나의 설계
김영권,이종규,전석빈,한종석,김준환 延世大學校 電波通信共同硏究所 1996 電波通信論文誌 Vol.2 No.1
Today's wireless communication needs the super-high speed for picture transmission and high-speed data transmission as well as voice. The optical(laser) communication is suitable for this demands because of the very wide optical bandwidth. But to fulfill the optical communication, the atmospheric attenuation of cloudy weather must be overcome. Under the weather condition of haze, fog, rain, and snow, the atmospheric attenuation, which affects on the optical satellite up-link communication between geo-satellite and earth station, was studied in this paper. In this case, the scattering attenuation and absorption is the most serious effect. The poiting error weaken the optical receiving power, too. These three attenuation factors directly influence the diameter of optical transmitting antenna. In this paper, the anttena diameter of the earth station was calculated according to the elevation angle, weather condition and transmission rate. The specification of this paper's simualtion was the 10[W] ?? laser as an optical source, and the binary FSK as a modulation method and the optical heterodyne receiver. The diameter of the optical cassegrain receiving antenna was assummed 1[m], the coding gain was set to 10[dB], and the BER(Bit Error Rate) was set to ???. As a result, the diameter of the transmitting antenna is distributed from centimeters to about 100 meters according to the weather condition, elevation angle and transmission rate. In case of the 10[Mbps] transmission rate, the receiving anttena diameter under the condition of haze is designed below 2[cm]. Fog makes the anttena diameter over 5[m]. Rain makes the anttena diameter below 3[m]. And snow makes over 10[m] anttena. Above values was calculated in the region of 30° ~ 90° elevation angle.