The standard of Wireless Metropolis Area Network, IEEE 802.16e, has mechanisms beyond the static standard, IEEE 802.16d, to cope with mobile nodes. One of the mechanisms is the handover procedure. Mobile node scanning of neighbor BSs in the IEEE 802.16e handover procedure has a procedure: Association. Association is an initial ranging procedure. The transmission is discontinued when a mobile node is scanning of neighbor BSs. Because initial ranging procedure is defined from the static standard, the delay time of association becomes a bottleneck of handover. One of the researches, NFHO (Network-assisted Fast Handover), proposes a method -¡¨Fast Association¡¨ to shorten the scanning time. In the method, the serving BS coordinates neighbor stations the exactly synchronization time for mobile node transmission of the initial ranging code. Another method of NFHO is to add an equipment, CSSC (Convergence Sublayer Switch Center). CSSC stores and broadcasts the data packets which are discontinued between handover. The metric proposed in this thesis called RAPHO (Rapid Association and Prediction-assisted Handover) which can shorten much scanning discontinued time. In one part of RAPHO, the serving BS takes the role of the mobile node to send the initial ranging code; in another part, the serving BS predicts the possible target BSs list. Because the mobile node doesn¡¦t participate in association and the number of scanning neighbor BSs is decreased, the improving scanning delay time of RAPHO is better than that of NFHO. According to the result of simulation, the total delay time (the scanning time plus the handover time) of RAPHO is better than that of NFHO.
| Identifer | oai:union.ndltd.org:NSYSU/oai:NSYSU:etd-0813109-153406 |
| Date | 13 August 2009 |
| Creators | Lin, Rang-fu |
| Contributors | Wei-kuang Lai, Jiunn-Ching Chen, Chin-shiuh Shieh, Yuh-chung Lin, Chen-Da Tsai |
| Publisher | NSYSU |
| Source Sets | NSYSU Electronic Thesis and Dissertation Archive |
| Language | Cholon |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0813109-153406 |
| Rights | not_available, Copyright information available at source archive |
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