Research On Access Algorithm For Aircraft In Integrated Ground-air-space Information Network

Integrated ground-air-space information network is a strategic infrastructure, which is consisted of different kinds of spacecrafts, hypersonic nearspace vehicles and stations.All terminals are at different heights and using different space links. Integrated ground-air-space information network is of great social,economic and military value on global remote sense ,observation and information transmission. Integrated ground-air-space information network consiste all kinds of terminals,whose communication demand are different. How to guarantee users'access QoS(Quality of Service)is the problem that must be solved by access algorithm.After satisfy commonly terminals'access capability,we discuss problems of the high-speed terminals access Integrated Ground-air-space Information Network and requirements of short access delay and high reliability.Firstly,we analyze the development status of integrated ground-air-space information network and introduce its characteristic,application foreground, organizational structure.Then we analyze the characteristic of access algorithms and switching technologies which are used in satellite communications.By analyzing the characteristic of communication environment in space,the adavantage and disadvantage of access algorithms are systematically discussed.Aiming at the long propagation delay, high bit error rate and time-varying of channel performance in integrated ground-air-space information network,we propose the random and reserve combine access algorithm.The algorithm consider the structure of integrated ground-air-space information network and reduce access delay of high priority terminal.By using multiple request mechanism and link test,the algorithm reduce the impact of bit error.Finally,this paper carry out the modeling and simulation to the proposed access algorithm based on the OPNET and STK simulation platform.We simulate access performance between aircraft and LEO(Low Earth Orbit) in the environment of the long propagation delay, high bit error rate and time-varying of channel performance in integrated ground-air-space information network.Simulation results show that the access delay of the proposed access algorithm is less than ALOHA algorithm.