由於在無線網路的環境中，節點只有有限的能源，如何節省能源使用一直是重要的議題。本論文中，我們提出一個可用在所有無線網路上，可有效減少能源消耗的路由方法，稱為EGR（Energy-efficient Geographic Routing）。傳統路由演算法產生原路徑後，EGR在原路徑中的每一段路徑中找適合的轉傳點，以達到節省能源的目的；另一方面，也考量了平衡能源使用以延長整個網路的可使用時間。而在每一段路徑中，使用無線電傳輸模組可計算出傳輸與接受資料所耗的能源，從而找到能代為轉傳資料的轉傳區域。在這個轉傳區域中的節點都能作為轉傳點，可節省整體的能源消耗；再考慮Energy-Proportional Principle (EPP) 後，會達到平衡能源使用的目標。
EGR可以輕易的和傳統路由演算法作結合，我們針對兩大類型的傳統路由演算法作了修改，其它路由演算法亦可在每一段路徑中考量EGR以達到減小能源消耗。最後模擬與分析結果，發現EGR的確有效的節省能源使用，也增長了網路的可使用時間。

We propose an energy-efficient geographic routing (EGR) mechanism which is generally applicable to reduce energy consumption in wireless communication networks. To assure load-balance and energy efficiency, EGR enhances traditional ad-hoc routing algorithms by constructing an initial routing path considering location information. Then, to further improve energy utilization it selects relay nodes of links on the initial path. The EGR finds an optimum relay node in a relay region between any two traffic nodes to conserve energy and balance traffic load. The relay region is derived from the radio propagation model constraining energy-saving when relaying transmissions between two nodes. Any node within this region is a relaying candidate to decrease total traffic energy consumption and to balance traffic load. According to the Energy-Proportional Principle (EPP), we propose an energy-saving criterion. To balance traffic load, the EGR follows the EPP and in the relay region selects the relay node with the highest score corresponding to the criterion. Compared to the traditional routing methods, EGR effectively utilizes energy and prolongs network lifetime.

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