近年來，可攜式設備的迅速普及，造成無線網路的需求與日俱增。由於MANET無線網路具有因應特殊環境而機動架構的便利性，於是有關此類無線網路的研究漸受重視。
行動設備的移動性讓網路拓撲結構具高度變化性，而使繞路協定面臨極大挑戰，且成為重要的研究議題。其中無基礎架構式網路中的需求距離向量路由協定(Ad Hoc On-demand Distance Vector Routing Protocol, AODV)是普遍被應用到的需求式路由協定。其利用跳躍節點數(Hop Count)做為最短路徑之度量標準，被應用於大部份的無線網路環境之中。但是，據此所選擇出的路徑，卻有可能不是最穩定的鏈結路徑。本研究根據前人研究結果，藉由參考接收到的訊號強度所得出行動節點間的連線時間(Link available time, LAT)，可當成另一個路由度量(Metric)選擇。本研究經過結合Hop Count與LAT值的演算法設計，改善原AODV路由協定的網路效能。
經過實驗模擬，以本論文的方法，可比原來AODV路由協定有較佳的Throughput及End to End Delay的效能表現，證明本研究的價值與可行性。

In recent year, the rapid popularization of portable equipments has made the demand of wireless network to grow day by day. Specially, the MANET gains the attention of public with its convenience in construction.
The movement of mobile equipments makes the topology of their network to change rapidly. By this, the routing of this kind of network face enormous challenge and its routing problem becomes an important research subject consequently. In all the proposed protocols, the AODV (Ad Hoc On-demand Distance Vector Routing Protocol) is applied to most wireless environments. With it, the shortest path from the sourece to destination node is chosen by the metric of hop counts. However, the chosen path with this metric may not be the stablest one. By the predecessor’s research results, the LAT (Link Availble Time) can be calculated by the strength of received signal and may be regarded as another usable routing metric for real time traffic (Ex:multimedia transmission). Then, this paper works on the improvement of AODV with a routing protocol with combining metrics of hop-count and LAT.
The simulation results show better throughput and end-to-end delay can be obtained comparing the original AODV. It also shows this new protocol is worthful and feasible.

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