無線感測網路(wireless sensor network)中最大化感測覆蓋面積是一項重要的討論議題。因為感測節點被隨機部署、能量耗盡或故障等原因，進而造成覆蓋空區面積(coverage hole area)的產生。為了維持整個網路的連結性和提高感測面積覆蓋區域，許多研究提出演算法來解決此問題。並且透過模擬方式針對演算法性能分析而獲得其相關參數及特性，進而比較演算法之優越性和缺失。
而NS2(Network Simulator)為一個近似於真實網路的模擬工具，對於不同的網路架構和拓墣，NS2都可以做彈性調整。因此本論文以NS2為主要工具，分別針對三個不同覆蓋空區的演算法利用NS2進行模擬，根據不同之模擬參數觀察各個演算法之特性和之間的差異性。

In wireless sensor networks to maximize sensing coverage is an important subject of discussion issues. Since sensor nodes are deployed randomly, energy depletion or failure, that cause to produce coverage hole area. In order to maintain the network connectivity and improve the sensing area of coverage region, many of the algorithms are proposed to solve related problems. Therefore, by simulation, performance analysis is obtained the relevant parameters and properties, and compares the advantages and drawbacks in algorithms.
The NS2 is similar real network simulation tool, and the NS2 simulation environment is flexible to investigate how various protocols perform with different configurations and topologies. Therefore, in this paper, based on NS2 as the main simulation tool, we aim at the three different coverage hole area algorithms simulation separately, and observe each algorithm characteristic and difference.

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