Network Architecture of the UMTS Space Segment

Synopsis: This paper presents a network and functional architecture for the UMTS space segment. The transport of user data is done using ATM up to the BTS in the terrestrial segment and up to the FES in the satellite segment. The UMTS procedures and services are controlled by the MSCPs at the level of the LE, CSS, FES, and eventually on board the satellites. Many control entities implemented at the level of the LE are radio technology independent and can be shared between all layers of the UMTS hierarchical cell structure, including the satellite segment. This architecture defines a generic interface between the access and core networks. Any mobile satellite or cellular access network can be connected to the UMTS core network without requiring a modification of the core network.