A New Location Management Scheme Based On Dynamics Group Users For Along The High-Speed Railway Network

As the rapid development of high-speed railway, the location management of communication system face a huge impact at the condition of high speed train. Current static position management strategy is no longer adapt to the current requirements because of its inherent weaknesses, we urgently need a communication system serve for it. With the limited fund, how to avoid location update frequently caused by fast-moving train, which caused border area decline suddenly in service capacity SDCCH congestion, it is a huge challenge to wireless communication system.. For the railway network, it is a great significance to the theory and practice for using appropriate location and management strategies to solve the system service capacity SDCCH congestion problem of declining.This paper introduces the basic theory of location management and the structure of location database and its layout modes, in this paper two basic operations of location management is provided that is location update and the main strategy of paging respectively and the advantages and disadvantages of various strategies.In order to reduce the short time sudden SDCCH congestion brought by high-speed mobile, special network for GSM users in high-speed train to move as a unit of collective movement, and moving fast, small amplitude, direction, and so on,at the same time take the cost factor into account, this paper propose the location management strategy based on Dynamic Packet. In order to reduce the number of peple needs update in unit time, group mobile users on the train, update them by group number. The introduction of improved selective paging scheme to avoid the delay caused by location update problem of low call success, at the same time reduce the paging cost. Paper described in detail the location and paging process based on the dynamic group location management. Simulation using C# and the results show that packet-based dynamic location management strategy has occupied a small number of SDCCH channel, and has the advantages of low cost of location management.Finally, proposed the GSM-R communication is the inevitable development trend for visitors to improve their communication condition, proposed a priority location management based on dynamic grouping policy which can not only reduce the location management costs, while can meet the needs of railroad applications that is reliability and real-time communication and ensure the visitor can communicate.