逄愛君臺灣大學:資訊工程學研究所江佳恩Chiang, Chia-EnChia-EnChiang2010-06-092018-07-052010-06-092018-07-052009U0001-2707200912441300http://ntur.lib.ntu.edu.tw//handle/246246/185381近幾年ZigBee協定在無線感測器網路中日益普及，使得ZigBee網路中的服務品質受到極大的注意。在此論文中，我們發現在ZigBee網路中，無法同時輕易提供低延遲的品質指標。我們提出一個可實際應用之ZigBee協定修改。們將我們的提議正式表示成一個排程問題，並證明此問題為NP-Complete。因此我們提出一個heristic演算法並在不同拓樸網路上進行模擬。模擬結果顯示我們的修正可提供比現有研究更好的延遲表現。In recent years, the ZigBee protocol has been increasingly popular inireless sensor networks (WSNs). The quality of service in ZigBee networksherefore raise lots of attentions. In this work, we identify that thehannel utilization and latency are two conflicting quality due to the Zig-ee specifications. And we propose a practial modificaiton toward theigBee protocol to mitigate the conflict.nd we formulate our proposal as a scheduling problem. Formal problemefinition is provided and proved to be NP-Complete. As a result, weelivered a heuristic algorithm and performed simulations on differentopologies. The resuls show that our scheme is able to offer better latencyerformance compared with existed work.List of Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . viist of Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . viihapter 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . 1hapter 2 802.15.4 ZigBee Networks . . . . . . . . . . . . . . . . . . 5hapter 3 System Model and Shared Active Period Scheduling . 9.1 System Model . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.1.1 Shared Active Period . . . . . . . . . . . . . . . . . . . 12.1.2 Feasibility of Shared Active Period . . . . . . . . . . . 13.2 Shared Active Period Scheduling Problem . . . . . . . . . . . 15.2.1 Overlap Active Period Ratio . . . . . . . . . . . . . . 19hapter 4 Heuristics for Shared Active Period Scheduling Problem 22hapter 5 Experimental Evaluation . . . . . . . . . . . . . . . . . . 25.1 Simulation Setup . . . . . . . . . . . . . . . . . . . . . . . . . 26.1.1 Cluster Tree Topology . . . . . . . . . . . . . . . . . . 27hapter 6 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . 30eferences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 311314880 bytesapplication/pdfen-US無線感測網路排程低延遲IEEE 802.15.4ZigBeequality of servicelatency minimization[SDGs]SDG16thesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/185381/1/ntu-98-R95922020-1.pdf