無線感測器網路需要維持滿足需求的感測範圍和週期性的回報或轉送封包到資料收集中心，由於電池容量的限制覆蓋率和存活時間是無線感測器網路中的兩個主要的問題，拓撲控制是一個有效增加能量效率和延長網路存活時間的方法，拓撲控制包含三個階段：感測器佈建、拓撲建立和拓撲維持。首先提出一個應用於感測器佈建階段的新型基於三個感測器的三角形分割的分部解決(divide-and-conquer)佈建演算法，並提出感測器效能量測方法使用於動態感測器派遣填補空洞的問題，分部解決佈建演算法可以將克服覆蓋空洞的問題，將多邊形的空洞分割成N個小三角形並能計算需要感測器的總共數量和其個別的X-Y座標。接著討論拓撲建立和拓撲維持兩個階段，提出建立一個可靠的拓撲用以增加網路到達機率和動態拓撲維持演算法，這個演算法可以透過多重階段能量閥值來平衡感測器的能量消耗，我們所提出的拓撲建立和拓撲維持演算法的優勢在於可降低感測器能量消耗和提升網路存活時間。
然而，有限的電池能量是網路存活時間的主要限制，為了能達到無線感測器網路的永續性，採用收穫環境能量用以供應感測器網路是一個新興的方式， 由於再生能源的低充電量和動態不確定性，能源收穫感測器無法提供足夠的能源用以維持永久系統操作，最後，我們設計一個新型永久的分散式拓撲控制演算法，主要的目的在於提供無線感測器網路的永久持續性和讓再生能源能有效運用， 這個演算法在每個感測器中執行並包含拓撲建立和拓撲維持兩個步驟，在拓撲建立階段，每個感測器節點選擇最常工作時間的父節點，並調整封包產生速率，而拓撲維持階段則在適當的時候驅動拓撲建立步驟並重新建立新的拓撲，這個新型演算法的優勢在於可降低感測器能量消耗、提升網路存活時間，並達到永久系統的目的。

A wireless sensor network (WSN) has to maintain a desirable sensing coverage and periodically report or forward data to the sink. Coverage and lifetime are two paramount elements in a WSN due to constraints associated with battery power. Topology control is an effective method of enhancing energy efficiency and prolonging network lifetime. The topology control consists of three phases: sensor deployment, topology construction and topology maintenance. We present a novel divide-and-conquer deployment algorithm based on the triangular form that is executed on the three sensors, in the first phase, sensor deployment phase. The mobile sensor dispatch scheme discuss the hole health problem by using sensor efficiency measure method. The divide-and-conquer deployment algorithm can conquer the coverage hole of each triangle of the polygon. The number of sensors and coordinates of all sensors deployed in the coverage hole of the polygon can be evaluated as well. In the topology construction phase and topology maintenance phase, we build a reliable topology to increase the network reachable probability and a dynamic topology maintenance algorithm, which can balance the energy consumption by using multi-level energy threshold. The superiority of the algorithms of topology construction and topology maintenance of our proposed is in terms of decrease average energy consumption and prolong network lifetime.
However, the limited energy of battery is the major limitations on operational lifetime. To ensure WSN sustainability, harvesting ambient energy to power WSNs is a promising approach. Due to low recharging rates and the dynamics of renewable energy, energy harvesting sensors are unable to provide sufficient energy for sustained operation. We design a novel perpetual and distributed topology control (PDTC) algorithm aims to ensure WSN sustainability and make the harvesting ambient energy usefully. The PDTC algorithm performs in each sensor consists topology construction phase and topology maintenance phase. In topology construction phase, each sensor selects the most appropriate parent node with maximal working time and adjusts the traffic generation rate of the sensor to achieve the system sustainability. In the topology maintenance phase, this work applies a topology maintenance algorithm to trigger the topology construction algorithm and re-build a new network topology when needed. The superiority of the PDTC algorithm in terms of energy efficient, network lifetime, and system sustainability.

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