在無線感測網絡中，barrier coverage是一個很重要的議題。雖然barrier coverage的議題進調查已被提出過了，以提高阻隔了無線傳感器網絡的覆蓋範圍小。在本論文內，我們將學習如何使用權力下放的mobile sensor，以達到最佳的barrier coverage。我們首先確定的速度和每個傳感器中的延遲時間，以保證可以形成阻擋層。然後，我們提出了一種基於預定義的重疊感應範圍。在本文中所取得的成果將提供重要的指導方針和見解屏障覆蓋的無線傳感器網絡的性能和網絡的生命週期。

Barrier coverage of a wireless sensor network (WSN) is a critical issue in military and other security applications, aiming to detect intruders that attempt to cross the deployed region. In order to support better flexibility of deployment location and improved coverage of the sensors, this paper uses mobile sensors to construct the barrier. However, addressing the mobility of mobile sensors in a distributed way is a major challenge of this issue. This paper determines the speed and delay time for each mobile sensor in a way to achieve least mobility of mobile sensors for constructing the barrier. Performance study reveals that the proposed approach of this paper outperforms the existing works in terms of the mobility distance, barrier forming time and network lifetime.

Table of Contents
Introduction 1
Related Works 4
Problem Formulation 7
3-1 Network Model 7
3-2 Problem Formulation 8
Cooperative Mobile Barrier 13
4-1 Phase 1: Initialization Phase 13
4-2 Phase 2: Wait-Move Phase 15
4-3 Phase 3: Check Phase 22
Conclusion 25
References 26
Appendix 28

List of Figures
Figure 1 State diagram of each mobile sensor 13
Figure 2 The sensing ranges of two sensors are overlapped 14
Figure 3 Mobile sensor mi executes the overlap adjustment task 20
Figure 4 The overlap adjustment task applied in more complicated situation 20
Figure 5 The time duration of t check 23

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