在能量限制的感測器環境中，傳感器節點必須以低佔空比方式運作。也就是說，能量收集傳感器網路裡，大部分時間感測器節點是保持在睡眠狀態，只有在通訊時醒來。在低佔空比的能量收集感測網絡裡，通信延遲時間是一個新的挑戰在傳感器網絡應用（例如，跟踪和警報）。在本文中，我們介紹了節點通訊延遲界限問題在能量收集的解決方案。首先提出「單播」方式的解決方案找出最小的延遲時間，再利用「廣播」的方式縮短延遲時間。最後利用「單播」和「廣播」方法進行模擬比較。「廣播」比「單播」方法還要好，減少更多的延遲時間。

In Wireless Sensor Network, sensor nodes must operate at a low duty cycle mode in energy restricted sensors environment.
Therefore, the sensor node remained in a dormant state most of the time and only to woke up when communication is needed in energy collected sensor network. 
The communication delay time is a new challenge for low duty cycle energy harvesting sensor network applications (for example, tracking and alert). 
In this paper, we introduce a delay bound node communication solution in energy harvesting network.First we proposed the "unicast" type of solution to identify the minimum delay time, and then we use "broadcast" approach to shorten the delay time.
 Finally, we compare the simulation results of "unicast" and "broadcast" method.
 "Broadcast" is better than "unicast" method reduced more delay times.

目錄
Acknowledgements ii
論文提要 iii
Abstract iv
第一章 緒論 1
1.1 前言 . . 1
1.2 研究動機 . . 2
1.3 研究方法 . . 3
1.4 論文架構 . . 5
第二章 背景知識與相關研究 6
2.1 低占空比 (low duty cycle) . . 6
2.2 單播 (unicast) . . 7
2.3 廣播 (broadcast) . . 8
2.4 感測器模塊的架構與運作方式 . . 9
2.5 感測器電量消耗的參數 . . 10
第三章 網絡模型 11
3.1 節點工作行程表 . .11
3.2 假設條件 . . 12
第四章 方法設計 15
4.1 單播 . . 15
4.2 廣播 . . 19
第五章 模擬評估 22
5.1 基本設置 . . 22
5.2 某段時間內的系統性能 . . 23
5.3 系統數據分析 . . 25
第六章 結論 31
參考文獻 32
附錄-英文論文 35

圖目錄
1.1 節點延遲界限百分比 vs 節點的延遲時間界限 . . 3
1.2 單播延遲時間示意圖 . . 3
1.3 單播傳遞到多個目的地 . . 4
1.4 廣播傳遞到多個目的地 . . 5
2.1 單播封包傳送的例子 . . 8
2.2 廣播封包傳送的例子 . . 9
2.3 感測器模塊的區塊圖 . . 10
2.4 感測器節點的電量表示法 . . 10
3.1 感測器節點工作行程表的例子 . . 12
3.2 網絡拓墣圖 . . 14
3.3 時序圖 . . 14
4.1 網絡拓樸圖延遲時間 . . 16
4.2 節點與延遲時間之樹狀圖第一步 . . 17
4.3 節點與延遲時間之樹狀圖第二步 . . 17
4.4 節點與延遲時間之樹狀圖 . . 17
4.5 節點 0 到所有節點的最小延遲時間 . . 17
4.6 節點 0 到所有節點最小延遲時間的拓墣圖 . . 18
4.7 網絡拓樸圖最小延遲時間 . . 19
4.8 廣播分群第一步 . . 20
4.9 廣播分群第二步 . . 20
4.10 廣播分群最小延遲時間 . . 21
5.1 簡化方案例子轉換成樹狀圖 . . 23
5.2 廣播方案的例子 . . 23
5.3 節點能量收集率的樣本 . . 24
5.4 模擬設置的網絡拓樸圖 . . 25
5.5 網絡拓樸的分層圖 . . 26
5.6 平均延遲時間 vs 分層 . . 27
5.7 減少的平均延遲時間 vs 分層 . . 28
5.8 模擬設置的網絡拓樸圖 2 . . 29
5.9 平均延遲時間 vs 第 n 個感測器 . . 29
5.10 廣播減少的平均延遲時間 vs 第 n 個感測器 . . 30

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