在本論文中，我們藉由對感測存活時間 (sensing lifetime) 的考量設計了在無線感測網路上感測器佈放的演算法。在許多的應用上，為了感測器佈放的簡便，感測裝置是被任意的散佈在欲觀察的區域，在感測器數量足夠的情形下，每塊區域面積中的感測器數目是幾乎相等的。然而，感測器中能量的消耗會因為感測器位置的不同而不同，造成這個原因的可能會是那區域的感測器必須傳送較多次的資訊或是一次傳送的距離較遠，所以傳送的能量消耗較大，導致該區域中感測器能量的消耗較劇烈，而造成該區域感測器較快死亡，此種現象會讓整個系統的涵蓋範圍在短時間內下降。為了獲得較久的存活時間，我們基於不同的路由協定提出不同的感應器佈放的演算法，我們將分別討論在無線隨意多跳躍 (multi-hop) 和 LEACH的路由協定下，會有不同的感應器分布密度。首先我們整個涵蓋區域劃分成很多小塊的區域，再找出每個小塊區域中所必須負責傳送的資訊量，根據資訊量的多寡會有不同的能量消耗，依據此能量消耗我們佈放不同的感測器數量在不同的小區域中，能量消耗越多的區域給予較多的感應器，反之，能量消耗較低的區域給予的感應器數目較少，目的在使得整個涵蓋區域中感測器的能量的消耗不會因為位置的不同而有改變。模擬的結果的顯示我們的方法和任意佈放比起來，我們可以大幅提升整個系統的存活時間。

In this thesis, we design the sensor deployment algorithm with the consideration of sensing lifetime for wireless sensor works, which is called lifetime-based deployment algorithm. With uniform sensor deployment distribution, based on different routing protocol could let sensors’ energy consumption at variance. Some sensors maybe die very soon and decrease sensing coverage because they must relay more information or their transmission range is larger. In order to avoid this situation, we deploy more sensors in this area and let sensors deployed in this area die later to maintain total sensing coverage. Our main objective is to propose new methods to search the optimum sensor deployment density based on different routing protocol, multi-hop and LEACH. Use an information outlook to calculate sensors’ energy consumption deployed in every belt with different distance from the server. According to the accumulated information flow, we can search the deployment density in every belt with different routing protocols. Simulation results show that our methods can maintain initial sensing coverage longer than uniform distribution.

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