Technology, Data Bases and Sys’j’em Analysis for Space-to-ground Optical Communications
نویسنده
چکیده
Optical communications is becoming an evereasingly import@ option for designers of spaceround communications links, whether it be for wnment or commercial applications. In this paper technology being developed by NASA for use in %-to-ground optical communications is presented. t, a program which is collecting a long term data : of atmospheric visibility statistics for optical )agation through the atmosphere will be described. ally, a methodology for utilizing the statistics of the ospheric data base in the analysis of spacc-tomd links will bc prcscntcd. This mcthodo]ogy takes account the effects of station availability, is useful m comparing optical communications with rowave systems, , and provides a rationale for t.hc blishing the recormncndcd link margin.
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