在車輛隨意網路下之繞徑機制探討

The Research of Routing Mechanisms in the Vehicular Ad Hoc Network

陳志昇(Chin-Sheng Chen)

指導教授 ： 吳和庭

國立臺北科技大學/電資學院/資訊工程系研究所/碩士(2007年)

摘要

近年來有關車輛隨意網路的研究發現，相同的繞徑協定在車輛隨意網路下的效能，遠不及在行動隨意網路下的效能，那是主要原因為車輛隨意網路有著一些與行動隨意網路不同的特性。
而本研究主要就是針對車輛隨意網路有著一些與一般行動隨意網路不同的特性，像是車輛在十字路口會因停交通號誌燈而使車子數量比較密集，單線道下常常後車會與前車保持等速且同方向前進等。探討前述的特性並分析結果來修正原本在行動隨意網路有高效能的繞徑協定，使之利用車輛隨意網路之特性來做到在車輛隨意網路中也能展現出高效率。
我們利用車輛行進的速度及方向，做為車輛群組的主要歸類依據，並讓繞徑過程中主要由同一車輛群組的移動車輛擔任資料轉送節點。如此，可形成比較穩定的繞徑路程，以增進繞徑效能。在本論文中，我們也建立了一個車移動的模擬環境，並將前述所設計之新繞徑協定應用於此車輛隨意網路，藉由模擬的結果來驗證本協定的效益與強健性。

關鍵字

行動隨意網路 ； 車輛隨意網路 ； 繞徑協定 ； 車輛移動

並列摘要

Recent research results have indicated that there exist significant differences of mobile characteristics between MANET and VANET environments. Therefore, those legacy routing protocols which are mainly designed for the MANET often cannot exhibit excellent performances when they are employed in the VANET topology.
In this thesis, we first analyze the distinctive features exhibited in the VANET environments. For example, vehicles tend to be close to each other near the intersection of the streets because of stopping for the traffic light. Vehicles often move in the same direction with the similar moving speed in the one-way street. We then utilize these characteristics to develop a corresponding routing protocol to be employed for the VANET environment. We classify each vehicle into its associated vehicle group according to the moving speed and direction. Vehicles belonging to the same vehicle group as the traffic source vehicles have higher priorities to act as the routing vehicles for message transfer. In this way, a more stable routing path can thus be constructed such that the routing performance is enhanced. Simulation results have justified the effectiveness of our proposed mechanism.

並列關鍵字

Mobile ad hoc network ； vehicular ad hoc network ； routing protocol ； vehicular movement

參考文獻

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