The signalling system in satellite personal communicatication networks.

Recent advances in both satellite and terrestrial mobile communications technologies are now leading to the realisation of the dream of the global personal communications within a few years. Satellite systems, as a complement to terrestrial cellular systems, are introduced into the future Personal Communication Networks (S-PCN) to provide global coverage and to allow global roaming. The inter-working and the integration between the satellite and the terrestrial cellular systems (e.g. GSM system) are the key issues in developing the network architecture and designing the control functions and signalling protocols of satellite systems. This thesis focuses on the design of a satellite signalling control system. The coverage and link properties of ICO10 and LE066 satellite constellations, the representatives of low earth orbit (LEO) and medium earth orbit (MEO) satellite systems, are considered. A satellite specific network architecture is proposed to accommodate the requirements of satellite dynamics and resource control function. The physical layer of satellite signalling links are designed to cope with the specific features of LEO or MEO satellite air-interfaces. In order to overcome problems specific to LEO or MEO satellite systems and to provide call set-up control function, three important signalling protocols are proposed for the S-PCNs. The priority based fast access scheme is designed for the satellite random access channel allowing low access delay for the call set-up related access packets, even when the channel load is high. The satellite diversity based paging approach is proposed to optimize the paging performance. The modified selective re-transmission (M-SRT) and Go-Back-N (M-GBN) protocols are proposed to cope with the transaction type transmission on the dedicated control channel. Simulation results have shown siginficant improvement of the M-SRT and M-GBN protocols in call setup delay. Two protocols are also compared in the aspects of implementation complexity and call set-up performance. Finally, the integration scenarios between satellite and GSM system have been examined for S-PCN in the call handling related functions and associated signalling protocols. The GSM higher layer signalling protocols are tailored to provide the call control related functions. The optimum integration scenario is derived under the criterion of minimum modifications to the GSM higher layer signalling protocols and minimum complexities of the control functions