Random Access Mechanism Of Satellite Communication System

With the continuous development of communication technology and the development of new businesses, the traditional terrestrial cellular mobile communication and optical fiber communication can't satisfy the people's communication for global coverage without blind spots, satellite communication as an important method of communication go into more people's vision. Building a satellite communication system and world of information infrastructure, will have significant benefits for the tradition-al Internet, Internet of things and military Internet.To a certain extent, Random access technology as the key technology of user access network, its performance directly determines the performance of the whole system. In satellite communication system,satellite as a forwarding node is far from the ground network, and the ground communication transmission delay is longer, in order to meet the business needs in system capacity and delay of the satellite communication, the research of random access procedure is one of the focus of the entire system.This thesis is based on the FX satellite communication system, the random access process conducted in-depth research and analysis, based on the random access procedure is designed to meet the satellite system,focusing on the preamble management mechanism and back-off algorithm. Firstly, this thesis introduces the random access protocol commonly we used, on the basis of the design the random access process of FX satellite system, and according to the system structure of the protocol stack, design the key signaling transfer nodes in random access process. In the management mechanism of the random access preamble,this thesis put forward three kinds of management scheme discuss, and through mathematical derivation and simulation comparison verifies the performance of access success rate. Research on back-off algorithm of satellite system, this thesis analyzes several common back-off algorithm,and through simulation in terms of delay and throughput are analyzed,based on discussing the back-off algorithm on the performance of choice as a binary exponential back-off algorithm in satellite system, base on this algorithm model, deduces the key parameters of the algorithm. According to the preamble management and back-off algorithm analysis, we can effectively solve the user access collision rate and delay requirements of users.