車用隨意網路之叢集化及功率指定設計

Abstract

隨著無線通訊網路技術的進步，加上電子元件價格漸漸下降以及行車安全問題越來越受重視，各國政府紛紛投入智慧型運輸系統(Intelligent Transport Systems, ITS)的研究。車用隨意網路(Vehicle Ad-hoc Network, VANET)，為當前了為實現ITS所發展出的重要網路架構。在個架構下，每一個搭載無線通訊設備的車輛，都可以透過路旁的路側系統(Road Side Unit, RSU) 連線到Server 端索取所需的資訊。而當車輛距離基地台太遠超出傳訊範圍時，也可透過其它的車輛幫忙轉送。換句話說，每一個車輛都可視為是一部行動無線路由器(mobile wireless router)。因此，這樣的架構可大幅提升網路建置彈性，只要有車輛的地方，即可是VANET的涵蓋範圍。 然而受限於無線網路本身的干擾問題(Interference)，傳輸路品質將受到週遭的傳輸情況所影響，再加上車用網路受到特定的車輛移動模式、駕使者行為、及高速行徑等因素的影響，使得網路品質難以掌握。有鑑於此，本計畫將為高速移動的車輛網路，設計以有效的叢集化(clustering)及功率指定(power assignment)方法，以減少網路干擾，進而提升流量產出及管理上的效果。

Owing to the dramatic cost down on electronic components and the advances on wireless technologies, the development of Intelligent Transportation System (ITS) has drawn intensive attention in recent years from many countries. The Vehicular Ad hoc Network (VANET) is a promising approach for the future ITS. In this novel network architecture, a communication is either enable between the vehicle and road side unit (RSU) or between any two cars in multihop fashion. In other words, the deployment is flexible and the network coverage can be easily extended to wild range. However, due the potential interference problem in wireless carry, the network quality would be severely deteriorated. On the other head, the unique features in vehicular network could introduce more uncertainty to the performance. In this project, we intend to develop clustering and power assignment mechanisms to reduce the interference problem in VANET