近來無線分封網路系統正以飛快的速度，蓬勃發展著。傳統聲音服務、無線服務的提供業者以及相關設備製造廠商，都盡全力地在追求著更快速的傳輸速度，希望能使蜂巢式網路使用者的傳輸速度，大幅度地提升。目前新一代的無線網路系統（如加強型整合性封包傳輸服務）的最主要的挑戰性在於如何對使用者提供不同等級的QoS（傳輸服務品質）。
在有線的網路系統中，傳輸服務品質的機制已被廣泛地討論與分析，同時專家們也都同意加權式公平排隊方法（WFQ）是最為眾人所知的排程演算法，而且相信其能提供有限制的延遲保證及有限制的輸出保證。然而要將在有線網路上的加權式公平排隊方法套用到無線網路上，卻不是一件顯而易見的工作。這是由於無線網路的特性，如爆發性地與位置相關的頻道錯誤和與位置、天氣相關的資料傳輸速度，所造成的結果。

在這篇論文中，我們提出三個最佳化的方法以及兩個去交換頻道的使用權，試圖在遇到錯誤與無錯誤的資料流之中作頻道使用權的交換。如此一來，資料傳輸速度的變動，與頻道發生錯誤的情形，能夠不被使用者所察覺到。同時達到提升頻道使用的效率，與兼顧使用者之間公平的頻寬分享。

第一個最佳化的方法是最大化效能、第二的方法是最佳化公平性，第三個方法則是結合效能跟公平性。這篇論文是用模擬的方式來做效能的分析。

Recently there has been a tremendous growth in the popularity of wireless packet switched networks. In addition to the traditional voice services, wireless service providers and equipment manufacturers are working hard on offering higher speed data access over cellular wireless networks. One of the key challenges of the next generation wireless networks (such as EGPRS) is the ability to provide different grade of QoS (Quality of Services) services to the users. In the wireline networks, the QoS mechanisms have been extensively studied and researchers have agreed that weighted fair queueing (WFQ) is
a popular scheduling algorithm to guarantee bounded delay, bounded throughput and fairness. However, adapting the WFQ scheduler to wireless networks is not trivial due to the bursty location-dependent channel errors and location-weather-dependent data rates. In this paper we propose optimal schemes that are based on combing WFQ with compensation technique which swap channel access among traffic flows that do and do not experience variable channel errors and variable data rates, so that the variable channel errors and data rates are transparent to the users.

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