A Design And Impelementation Of Mobility Management In LEO Satellite Networks

With the development of communication technology, people’s demands become more and more various and higher. Even though the high quality of communication technology is essential for the new business, the cost also need to be considered. Due to the restrictions of technical level, economic and environmental conditions, and such noticeable reasons, the ground base stations are usually built in the populated areas, and not in the remote areas or islands. Meanwhile, in the poor environment such as desert, lake, sea and so on, the difficulty of constructing a station is impossible. Furthermore, in the natural disasters such as earthquake and tsunami, the station may suffer bad damage and couldn’t provide services. Therefore, satellite communication draws more and more attention because of its remote communication distance, wide coverage, high reliability and quality.The research of this paper is mainly based on LEO satellite network.To the point of the limitations of the existing mobility management technology in LEO satellite, this paper proposes a new mobility management scheme based on identity and position separation. Firstly,the scheme refers to the idea of identity and position separation, designs a new way of addressing, that is partition to the surface of the earth and the user’s address is composed of the area ID and user ID. Then to ensure a one-to-one correspondence between the satellite and the ground partition,we put forward a method to modify the satellite’s longitude and latitude.Using this method, we could make full use of regularity and periodicity of the satellite motion, effectively save the limited storage space on satellites. Furthermore, in the case of large users, compare to the look-up table, the time delay caused by calculation will be more shorten, and has more advantages. Using the satellite to ground map, each user’s address consists of two parts, the area ID and user ID. Satellites need to maintain two tables, one is the map between the partition and the satellite, the other is routing table. Then the paper describes the specific handoff and communication process of this mobility management scheme. At the same time, we describe an integrated process of handoff and communication using this scheme, and finally conduct simulation experiments using QualNet and STK and analysis the results such as the delay and the packet loss probability.According to the experiment results, it proves that the mobility management scheme based on identity and position separation could support mobility. At the same time, the delay always keep stable, and could effectively avoid the problem of ’Triangle Routing’. In the end, we make a conclusion of this paper, and analysis the benefits and limitations of this scheme and the future research of optimization.