• 제목/요약/키워드: soft handoff zone

검색결과 2건 처리시간 0.021초

몬데카를로 소프트 헨드오프 모델링 (Monte Carlo Soft Handoff Modeling)

  • 추현승;정민영;홍인기
    • 한국시뮬레이션학회논문지
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    • 제13권1호
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    • pp.1-9
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    • 2004
  • In this paper some models for obtaining the distribution of a sojourn time in CDMA cellular systems are proposed. Knowledge on this is essential for reliable modeling of the soft handoff and for solving other related problems in the analysis of cellular system. The proposed model is based on random walk and can be adopted to different conditions. Analytical results can be obtained that lead to a quite complicated numerical scheme so simulation models are used for Monte Carlo experiments. Main assumptions include different kinds of mobile carriers (pedestrians and transport passengers) and round shape of a cell. The scheme for simulation experiments is presented along with the discussion of simulation results.

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Mobility and QoS Support in 4G Wireless Networks

  • Kim Taehyoun;Lee Jaiyong
    • Journal of Communications and Networks
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    • 제7권2호
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    • pp.178-191
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    • 2005
  • Fourth-generation (4G) wireless networks will be the IP-based cellular networks integrating Internet with the existing cellular networks. Two important issues should be concerned in the IP-based cellular networks, IP mobility, and quality-of-service (QoS) guarantees. In this paper, we proposed two mechanisms to solve the problems with IP mobility and RSVP-based QoS provisioning. First, virtual-IP (VIP) allocation scheme in areas with a large rate of handoff can minimize the wireless signaling overhead due to IP mobility. The access routers (ARs) create dynamically the VIP zone by using the measured handoff rate derived from the history of the handoff into neighboring ARs. We show that VIP allocation scheme reduces the binding update messages in the wireless link than hierarchical mobile IPv6. Second, the new advance resource reservation protocol called proportional aggregate RSVP (PA-RSVP) can minimize waste of bandwidth and soft state refresh overhead due to IP mobility. It allocates the bandwidth in advance between the mobility anchor point and neighboring ARs using proportional aggregate reservation. We also show that PA-RSVP provides an improved performance over existing protocols.