WCDMA與WLAN異質網路之適應性磁滯垂直換手之效能研究

Performance of Adaptive Hysteresis Vertical Handoff in Heterogeneous Networks of WCDMA and WLAN Systems

許晉維(Chin-Wei Hsu)

指導教授 ： 謝政勳

朝陽科技大學/資訊學院/資訊工程系/碩士(2009年)

摘要

本論文主要是探討WCDMA（寬頻分碼多工存取）與無線區域網路(Wireless LAN)之異質網路之垂直換手(Vertical Handoff)機制之效能，我們比較了固定式磁滯值(Fixed Hysteresis)垂直換手以及適應性磁滯值(Adaptive Hysteresis)垂直換手之效能。此外，我們進一步將頻寬分區，並且針對不同速度以及依據使用者不同需求來做頻寬的分配，由模擬結果可知，雖然固定式磁滯值垂直換手可降低乒乓(Ping-Pong)效應影響，但也使得系統流量受到影響；而適應性磁滯垂直換手不只降低乒乓效應，也能提升整體系統流量。

關鍵字

系統流量 ； 乒乓效應 ； 異質網路 ； 垂直換手 ； 適應性磁滯

並列摘要

This thesis explores the performance of adaptive vertical handoff schemes for overlaid WCDMA and wireless LAN (WLAN) heterogeneous networks. We propose an adaptive hysteresis vertical handoff scheme to effectively adjust the hysteresis to compromise the handoff rate and bandwidth. Simulation results show that the proposed Adaptive hysteresis Vertical (AHYV) handoff scheme can increase lots of average data rate than the fixed hysteresis vertical handoff scheme. Furthermore, with quality of service (QoS), we model three service by video, talk and internet services. Moreover, for three type mobility users with0, 10 and 60(km/hr), we design QoS based AHYV (QAHYV) schemes to compromise the handoff rate and system bandwidth. Simulation results show that the proposed QAHYV can not only reduce the handoff rate but also maintain the demanded QoS bandwidth for different mobile users.

並列關鍵字

handoff rate ； Quality of service (QoS) ； Vertical handoff ； Adaptive hysteresis ； Heterogeneous networks

參考文獻

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