Analysis On Satellite-ground Link Characteristics And Design And Implementation Of It’s Simulator

In space networks, building a space network emulator is very critical to debug, testand evaluate novel proposed protocols. Within a space network emulator, the linkemulation technology is one of the key technologies. Compared with the traditionalterrestrial link, the satellite-ground link has a significant difference in several properties,including long delay, high error ratio, bandwidth asymmetry, etc. These differences givea critical impact for the performance of space network protocols. Therefore, modelingand emulation of the satellite-ground link is an important challenging research topic.Towards research on satellite-ground link characteristics and design andimplementation of it’s simulator, we foucus on analysis and modeling of characteristicsof satellite-ground link, and implementation of satellite-ground link simulator based onthe NetMagic hardware platform. The main research efforts of the paper can besummarized as follows:Firstly, the paper analyzes the recent research efforts on satellite-ground linkmodeling and simulation, especially satellite-ground link models, link simulationtechnology and the mainstream link simulation tools.Secondly, analysis and modeling on the principal attributes of satellite-ground link.The paper proposes a new delay model for satellite-ground link, it spreads thetraditional path delay to processing delay and transmisssion delay, the final model ispresented in the form of fixed dealy plus varied delay. The bit error model ofsatellite-ground link is built on the comprehensive analysis of vario us environmentfactors, finally calculation formula of BER is given based on link power budget analysis.According to test reports, the delay and bit error model of satellite-ground proposed inthe paper accords with the actural case well, and canbe used as an effective tool insatellite-ground link design and analysis.Thirdly, based on NetMagic platform, we design and implenment a satellite-groundlink simulator which can give a real time simuliton of link off, bit error, delay andbandwidth characteristics in a satellite-ground link.Finally, we construct a simulation environment for satellite-ground link, and testthe function and performance of the simulator in detail. According to the testing results:the simulator gives high-precision simulation and real time control to link off, bit error,delay and bandwidth characteristics in a satellite-ground link.