隨著無線感測網路的應用增加，無線感測網路的佈建策略必須同時滿足各種需求，例如維持感測器節點間的網路連線、使感測器的感測覆蓋率達到最大，以及使感測器節點的使用量達到最小等等。本論文著重於在已知感測器節點的可用數量下，計算出感測器節點的佈建位置，使佈建區域達到最大的感測覆蓋率並維持感測器節點間的網路連通。為了計算出正確的感測覆蓋率，感測器覆蓋區域模型的正確性便十分重要。對於具有全向性感測區域的感測器節點，本論文提出兩階段的DT-Score佈建策略。第一階段針對佈建區域的邊界以及障礙物四周的覆蓋漏洞，藉由沿著佈建區域或障礙物輪廓佈建之感測器節點加以消除；第二階段利用Delaunay三角化方法以及評分機制佈建剩餘之感測器節點，達到最大的感測覆蓋率增益。對於具有指向性感測區域的感測器節點，本論文提出了多邊形覆蓋區域模型以及兩種相對應之Polygon-Random與 Polygon-Tiling佈建策略。多邊形覆蓋區域模型包含一連串以極座標表示之多邊形頂點，以逼近實際的感測區域。Polygon-Random佈建策略是從數個隨機產生的候選位置中，經由網路拓樸管理及評分機制選出最適合佈建新節點的位置。Polygon-Tiling佈建策略則是先從多邊形覆蓋區域模型表示之感測區域中生成內接凸六邊形，並將此六邊形透過鑲嵌方式填滿佈建區域。根據模擬結果，本論文提出的DT-Score佈建策略相較於基於網點或隨機的佈建策略，在充足的感測器節點下可達到完全的感測覆蓋率。此外本論文所提出的多邊形覆蓋區域模型以及相對應之Polygon-Random與 Polygon-Tiling佈建策略，則在感測覆蓋率以及感測器節點的使用量上，優於現有基於圓盤模型或是扇形模型的佈建策略。

With the increasing applications of the wireless sensor network (WSN), a WSN deployment strategy has to fulfill various requirements, such as keeping the network connected, maximizing the sensing coverage rate, minimizing the usage of sensor nodes, etc. In this dissertation, we focus on the connected area coverage problem under the deterministic WSN deployment. That is, given deployable sensor nodes, we want to determine the locations of sensor nodes to achieve maximum sensing coverage rate of deployment area and maintain network connectivity. To determine a correct sensing coverage rate, the accuracy of the sensing area modeling is significant. For sensor node with omnidirectional sensing area, we proposed a two-phased DT-Score approach. In the first phase, the coverage holes near the boundaries of the deployment area and obstacles are eliminated by deploying contour sensor nodes. The remaining sensor nodes are deployed based on the Delaunay triangulation and scoring mechanism to achieve the most sensing coverage gains. For sensor node with directional sensing area, we proposed the polygon model and corresponding Polygon-Random and Polygon-Tiling approaches. The polygon model consists of a list of vertices in polar coordinates used to outline the actual sensing area of a sensor node. The Polygon-Random approach deploys a sensor node to the location selected from randomly generated candidate positions through topology control and scoring mechanisms. The Polygon-Tiling approach fills the deployment area with convex hexagonal tiles and each tile inscribes the sensing area represented by the polygon model. According to the simulation results, the proposed DT-Score approach can achieve full sensing coverage compared with the grid-based and random-based deployment approaches under sufficient sensor nodes. The proposed polygon model and the corresponding Polygon-Random and Polygon-Tiling approaches outperform the existed disk model and sector model based approaches in terms of the sensing coverage rate and the usage of sensor nodes.

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