為了防止入侵者破壞重要的設施或是軍事區域，大量的無線感測器佈署在一個細長帶狀區域中進行入侵偵測。此種技術應用稱為障礙物覆蓋(Barrier Coverage)。本篇論文利用方向性感測模型，以理論為基礎發展了鋪設障礙物覆蓋的方法，並且在隨機佈署的無線感測網路上，提出了建構k 障礙物覆蓋的機制。此障礙物覆蓋機制已成功的實作在NS2 網路模擬器上，並且與全向性感測模型作比較。模擬的結果顯示，相較於使用全向性感測模型，方向性感測模型可以在相同的感測能量下，以較少的無線感測器來達成障礙物覆蓋。且在相同的環境設定下，方向性感測模型比全向性感測模型有更高的比例能成功建造障礙物覆蓋。

In order to protect significant facilities or military area from the intruders, hundreds or thousands of microsensor nodes could be deployed in a long thin belt to detect intrusion attempts. The application in wireless sensor networks (WSNs) is referred as barrier coverage. Previous research used an omni-directional sensing model for the barrier coverage. This thesis makes use of directional sensors to construct k-barrier coverage of a
belt region. In the thesis, theoretical foundations for laying barriers with the directioanl sensing model is developed. A mechanism for randomly deployed wireless sensors for k-barrier coverage is also implemented. Both omni-directional and directional models for the barrier coverage are evaluated with with the network simulator, NS2. The results demonstrate that less active sensors are needed to perform task for barrier coverage with
directional sensing model based on the same sensing energy consumption.

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