High-level Transmission Control Protocol And Multi-beam Handover Technology For Satellite Mobile Communication

With the increasing demand of users to the communication bandwidth,quality and coverage area,the current land mobile network faces severe problems,such as narrow coverage,higher costs in base station constructions and poor quality of communication.Consequently,the broadband satellite communication network,which is reliable,cost-effective,wide coverage and stable,is a research hotspot in the industry and academia.Based on the core technology of the 4th generation of cellular mobile communication system,the next generation of broadband satellite mobile communication system will be broad band,all-IP,try to improve the whole system's spectrum utilization and transmission rate.However,considering the difference of the system environment,the transmission control protocol applied in the ground wireless communication cannot be directly applied to the satellite communication.Based on the project from the laboratory,the author takes multi-beam switching technology and high-level transmission control protocol mechanism in broadband satellite communication systems as research project.The main contributions are as follows:1.Focus on the analysis of satellite multi beam antenna technology,a brief summary of the broadband satellite mobile channel characteristics and mobile channel model.A new model of the main and auxiliary multi beam satellite structure is proposed,and the corresponding simulation analysis is given.At the same time,a channel borrowing scheme is proposed.2.This paper introduces the main working mechanism of TCP,and analyzes the influence.On the one hand,from the point of view of protocol,the improved scheme is put forward,and the corresponding simulation analysis is given.Furthermore,combining with the MAC layer information,analyzing the causes of link congestion,the implementation of congestion control algorithm is proposed,and the transmission efficiency of TCP is improved.3.On the other hand,from the perspective of the satellite link,which is kept to be "transparently",and a kind of optimization scheme is proposed.Protocol gateway to the ground terminal TCP protocol conversion and maintain the connection "transparent",reduces the cost of hardware transformation,not only has a better compatibility,but greatly improves the bandwidth utilization rate of broadband GEO satellite communication system.