在無線感測器網路下，由於感測器彼此之間可能會使用不同的傳輸功率或是感測
器傳輸範圍不固定亦或是一些隱藏節點的問題導致單向連結的生成。因此針對這
個問題，我在這篇論文裡提出了一個預先建構圖形的方法，使得平面路由協定能
成功使用，而這個方法只需要針對原先存在單向連結的無線感測器網路拓樸便可
使用；此外，我更提出了一個新的地理位置路由協定，稱作Directed Greedy Face
Greedy (D-GFG)，並將這個方法套用在生成的圖形上。這個路由協定不僅能夠不
靠著計算和儲存全域性的拓樸資訊來達到保證傳輸，而且，借著我提出的平面採樣
方法，D-GFG甚至能提供傑出的路由效能。在實驗方面，我評估了以下幾個路由
協定的效能，分別是D-GFG, GOAFR+, GPSR, GFG以及使用歐幾里德度量的貪
婪路由，從結果可以發現我的路由方法在任何情況下都能展現相當優良的效果。

A wireless sensor network has unidirectional links because sensors can have dierent
transmission ranges, sensors have unstable transmission ranges, and a hidden termi-
nal problem exists. In this thesis, I introduce a pre-construction protocol to construct
graphs based on the network topology to make face routing usable on the wireless sen-
sor networks with unidirectional links, and I propose a geographic routing, Directed
Greedy Face Greedy (D-GFG), which routes packets on these graphs. My routing
protocol guarantee packet delivery without computation and storage of global topol-
ogy features. Furthermore, the performance of D-GFG is excellent after applying the
sampling procedure. Using the simulation, I evaluate the performance of the proposed
routing protocol(D-GFG), Greedy Other Adaptive Face Routing (GOAFR+), Greedy
Perimeter Stateless Routing (GPSR), Greedy Face Greedy Routing (GFG), and the
greedy routing protocol based on Euclidean distance. The simulations demonstrate
that our routing protocol ensures moderate routing path length.

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