Terminal⁃to⁃Terminal Calling for GEO Broadband Mobile Satellite Communication

[Abstract] Satellite and terrestrial components of IMT⁃Advanced need to be integrated so that the traditional strengths of each component can be fully exploited. LTE/LTE⁃A is now a recognized foundation of terrestrial 4G networks, and mobile satellite networks should be based on it. Long transmission delay is one of the main disadvantages of satellite communication, especially in a GEO system, and terminal⁃to⁃terminal (TtT) design reduces this delay. In this paper, we propose a protocol architecture based on LTE/LTE⁃A for GEO mobile satellite communication. We propose a detailed call procedure and four TtT modes for this architecture. We describe the division of tasks between the satellite gateway (SAT⁃GW) and satellite as well as TtT processing in the physical layer of the satellite in order to reduce delay and ensure compatibility with a terrestrial LTE/LTE⁃A system.

[Keywords] TtT call; LTE/LTE⁃Advanced; satellite communication system