低功耗無線傳感器節點的能量采集

　　今天，無線傳感器網絡（WSN）正在尋找一個廣泛的消費，醫療和工業應用。一個慢跑者現在可以穿一個藍牙胸帶，能讓她的心率跑步機或無線上傳全部的鍛煉她的PC和引導她通過她的iPhone。為慢跑者的年齡，她可以穿無線心電圖（ECG）補丁傳遞她的心臟活動的醫生。

　　從健身房回家的路上，我慢跑駛過一座橋的病情監測的無線傳感器網絡監測應變、開裂、磨損。頭頂上的飛行是一架飛機，其機翼是由壓電能量采集器驅動的無線傳感器網絡不斷監測的機械應力。她在加油站短暫停了一下，因為一個無線輪胎壓力監測器（TPM）顯示輪胎很低。回到家中，她配備的ZigBee智能電表一直在監測家庭的能源使用情況，提供反饋幫助她減少電費。

　　All of these applications involve wireless sensor nodes that – with the possible exception of the smart meter – would do well to run for years between battery replacements. This can be achieved only by the use of energy harvesting， utilizing ambient sources to prolong the life of the batteries in wireless sensor nodes.

　　In this article we will examine the various ambient power sources available for energy harvesting and evaluate whether they are likely to prove adequate to power low-power wireless sensor nodes.