• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 1
  • 1
  • Tagged with
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

第三代行動通訊系統中利用位置預測以改進交遞管理之研究 / Location Prediction for Handoff Management in 3rd Generation Mobile Communication System

徐榮志, Roger Hsu Unknown Date (has links)
目前全球電信業的發展,將以第三代行動通訊網路(3G)為基礎,有效提供全方位的無線寬頻數據與語音服務。而IP(Internet Protocol)的應用與行動通訊的結合,將會徹底改變大眾未來的生活。在第三代行動通訊網路的發展中,因為基地台的涵蓋範圍愈來愈小(micro/pico cellular),造成使用者在使用行動通訊網路時會產生更頻繁的交遞。如何讓使用者在進行交遞程序時降低交遞失敗率(handoff dropping rate),讓使用者在使用第三代行動網路的服務時,不會因為交遞的發生而造成服務中斷,以達到無接縫的交遞(seamless handoff),並同時降低新呼所堵塞率(new call blocking rate)及滿足各種使用者需求的服務品質,提升資源使用效率。本論文考量以使用者位置(location-base)及基地台特色作為交遞預測的準則。以往,交遞執行與否的決定是以使用者設備接收各基地台訊號強弱、移動速度等資訊作為參考。在此我們利用已發展出之各種定位技術,以使用者位置做為交遞程序準則(location-aware handoff),根據每個基地台在不同地理位置所呈現出的不同訊務特色,提出一個適用於各種環境,在交遞時的資源保留機制。預測使用者的未來走向,以滿足使用者在交遞時QoS的需求,使得在基地台中資源預留達到最小,能有效降低新呼叫堵塞率、交遞失敗率,並提升基地台資源使用率,進而使整個網路效能最佳化,滿足各種服務之QoS需求。為驗證本文所提出的交遞及資源保留演算法對於系統效能的改進,在此設計了一套適用於第三代無線通訊網路的交遞模擬系統。使用者可匯入不同地區的實際電子地圖,系統會依使用者在不同位置所產生之不同的行為模式,如方向、速度等;或因基地台之地理位置及時間的不同,產生不同的使用需求或訊務量等;據此建立各個基地台的使用特性,以符合實際使用狀況,並獲得更精確的模擬結果。末了再套用本文所發展的交遞及資源保留演算法修改模組,以驗證不同交遞演算法及通訊協定的效能。 / The development of mobile communication will base on the 3rd generation communication system (3G), which can provide boardband wireless data communication and voice service. The integration of Internet protocol and mobile communication will totally change our future life. In comparisons with previous mobile communication systems, the coverage of 3G base station is much smaller, which will cause Mobile Host (MH) execute handoff procedure more frequently. Our goal is to reduce handoff dropping rate, new call blocking rate and at the same time satisfy all QoS requests, increase resource utilization supporting seamless handoff. In the past, handoff procedure is executed by assessing signal strength of base stations. Here we consider user location and base station geographical pattern to support a location-aware handoff procedure. We invent a resource reservation scheme according to the traffic characteristics and environment of the base station and predict user location to optimize system performance. To compare the system performance between different schemes, we developed a handoff simulation tool (3GHOSim) suitable for 3G mobile communication system. The system could import electronic map, create different user behavior (direction, speed, etc.), generate different user requirements and traffic loads trying to get more realistic simulation results.

Page generated in 0.0224 seconds