A Model of Addressing Abnormal Users in IP/LEO Satellite Communication System Based on Geographical Information Subnet

Abstract

The geographic information-based subnet partitioning scheme provides the basis for satellite-ground integrated addressing. Meanwhile, this scheme will inevitably cause addressing abnormal users (AAUs), i.e., the satellite which has address convergence relationship with users' co-subnet and the satellite which users actual access to may be different. This problem will decrease the network communication efficiency. With the aim of quantifying the statistical variation pattern of AAUs to reduce the impact, this paper constructs a statistical model of AAUs under the general closed geographic partition shape. Further, considering the orbit characteristics and the uniform rotation of Earth, this paper derives an analytic formula for the average addressing abnormal user rate (AAUR) under circle and polygon geographic partition. Meanwhile, by simulating a specific LEO satellite constellation, this paper obtains the temporal average of AAUR in spherical trapezoidal partition during one orbital period, which is sufficiently approximated to the result of analytic formula, verifying the validity of this model. The model shows that the average of the AAUR decreases gradually as the ratio of satellite coverage area to geographic partition area increases. When the ratio is greater than 1.6, the average AAUR is less than 5%. The research work in this thesis quantifies the relationship between the average of the AAUR and satellite to earth communication range, geographic subnet range, geographic subnet shape, which can provide a reference for the matching design of geographic partitioning under any constellation configuration.