無線感測網路的覆蓋度、部署與系統生命週期之研究

Abstract

在無線感測網路中，當一個感測節點處於啟動狀態，有三個主要的工作:感測、傳輸資料、以及接收資料。其中，傳輸資料包含了傳送自己所感測的資料，還有轉送來自其他節點的資料。顯然的，這些工作都需要消耗電量，每個節點的電量是受限制的，以致於系統時間也會受到限制。然而許多的無線感測網路應用系統，像是追蹤監控，就會需要整個系統達到一定程度的覆蓋度。於是我們將系統的生命週期定義為，當無法達到系統覆蓋度或是網路連通性時，生命週期結束。許多研究指出，無線感測網路的系統生命週期和覆蓋度有相當程度的關連。另一方面，也有許多著眼於能提升無線感測網路系統生命週期之部署方式的研究。本研究的目標則是，設計一個實際的考慮系統覆蓋度的睡眠排程演算法，同時以一個能提升無線感測網路系統生命週期之部署方式配合之。

In wireless sensor networks, when a sensor node is active, it has three main tasks—sensing, transmission, and receiving. (Transmission includes sending self-generated data and forwarding data from other sensor nodes). Obviously, these tasks consume energy, so that the system lifetime of the network is limited. While many applications such as tracking and surveillance require a certain level of coverage, the system lifetime can be simply defined terminated when the required level of coverage can not be achieved or when the nodes can no longer connect to one another. Many research results have revealed that the system lifetime of sensor networks are related to how the level of coverage is required. On the other hand, some works focused on the energy-efficient nodes deployment strategy. Our objective is to a design a practical coverage-aware sleep scheduling algorithm and a strategy of nodes deployment that can extend the system lifetime.