隨著無線網路的蓬勃發展，研究人員為提高網路傳輸的服務品質，不斷地找出解決方案以因應各種不同的狀況發生，網路模擬軟體即是一套輔助的工具用來協助研究人員現實網路中的頻頸所在，在本論文中所採用的網路模擬軟體為NS2，它的原始碼是開放的，因此可於其上延伸其它功能，在本論文引用了瑞典Lulea大學計算機與網路學系提供的相關Open source，並作了缺失的改進，作為第四章實作的基礎。
有線網路中常常有不可預期的channel error產生，造成Real-Time系統的網路服務品質降低，無線網路也有同樣的情形發生，因此我們目前遇到的問題是如何對網路上傳送的封包給於公平的排程並達到系統最大效能。在本篇論文中利用在NS網路模擬軟體上所延伸的PCF（Point Coordination Function）作業方式來模擬二個Real-Time packet scheduling演算法，根據模擬的結果作為未來演算法可改進的方向。

As the wireless network develops quickly, more and more creative technologies have been invented. In order to provide higher quality of service, the researchers have to understand where the problems are. So a network simulator is a very helpful tool for them to study. NS2 is a very famous network simulator and widely used. It’s open source. Any one can extend needed functions over it. The thesis implements the PCF protocol referencing the contribution of Anders Lindgren and Andreas Almquist, Lule, University of Technology and fixes some bugs. It is the basis of the implementation of chapter 4.
As the unpredictable channel errors occur during the packets transmission in wireless network, the quality of service is degraded. The problem that we have to face is how to schedule the traffic fairly and maximum the system throughput. In this paper I implement two Real-Time packet scheduling algorithm and simulate channel errors in NS2 network simulator. According to the result of simulation, it can be the directions of improve the algorithm in the future.

1. Tutorial for the Network Simulator “ns” http://www.isi.edu/nsnam/ns/tutorial/index.hm/
2. WPI WORCESTER POLYTECHNIC INSTITUTE Computer Science, NS by Example, Jac Chung and Mark Claypool, http://nile.wpi.edu/NS/
3. Learning NS Website http://netlab.cse.yzu.edu.tw/ns2/ns2_website/
4. The Rice University Monarch Project : Mobile Networking Architecture, http://www.monarch.cs.cmu.edu/
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7. contributions to the network simulator ns2 http://www.sm.luth.se/~dugdale/index/software.shtro/