無線感應器網路(Wireless Sensor Network)由許多無線感應器(sensor node)組成，感應器主要是在特定的感應範圍內監控某物體或環境的變化，感應器經由無線感應網路傳回感應結果給使用者，在民生、軍事、航太或是醫學都有廣泛的應用。其中許多的應用，無線感應器呈規則排列，像是生醫感應器，這類的感應器節點的的特性是位置為固定，而且我們可以事先決定它的位置。感應器由於需要長時間的使用，如果要節省電源的消耗或是增加網路的使用時間就必須對電源有效的管理，而一個感應節點最耗電源的部分就在無線電傳輸，所以節省電源的最好方法就是完全關閉無線電的傳輸，也就是切換至電源節省模式(power saving mode)。這篇論文裡，我們在四種規則的無線感應器網路，利用connected dominating set的概念設計我們的通訊協定，我們對於每種圖形選擇數個connected dominating sets，讓這些dominating sets輪流切換至電源節省模式，我們試著讓每個connected dominating set最小，並且讓每個節點能平均消耗電源，來達到減少節點電源的消耗而且延長網路使用時間的目的。根據模擬與分析的結果證明我們的通訊協定利用額外的傳輸時間來節省無線感應網器路總電源的消耗與延長網路的使用時間，無線感應器網路管理者可以根據我們分析結果，建構合適的網路架構。 The wireless sensor networks (WSNs) have attracted lots of attention recently. Since the wireless sensor node has no plug-in power, we have to conserve power so that each node can operate for a longer period of time. The best way to conserve power is to let the sensor node switch to power saving (PS) mode. When some nodes switch to PS mode, the network still need to be connected so that the sensed information can be sent to the base station through the active nodes. Here, we propose several power management protocols based on the idea of connected dominating set. We choose several connected dominating sets for each network topology. These connected dominating sets will switch to active mode in turn to serve other PS nodes in the WSN. We try to minimize the size of each connected dominating set and balance the power consumption of each sensor node, so that we can extend the life time of the WSN. Numerical analysis and simulation results show that our power management protocols can conserve lots of power and greatly extend the lifetime of the WSN with a reasonable extra transmission delay.
