以安全、節能及遊憩為目的之車載網路系統---總計畫(I)

Abstract

本整合型計畫之目標，為建立一個智慧型的車載資通訊網路平台，除了考量人、路、車的管理策略，並增進運輸系統的安全、節能與效率，以及行車舒適性的同時，也結合各種交通工具以達到導覽遊憩的應用。此車 載資通訊網路平台涵蓋自應用層而下至媒體存取層，其整體分工為「車載資通訊服務及其應用系統」與「車載網路通訊核心技術」兩大方面。 子計畫一「車群管理服務：行車節能與共乘系統」提出以車輛群組的概念，設計互動式的交通控管機制，目的為提升道路的使用度，並減少車輛加減速次數使整體交通流暢，進而達到節能與環保的效益，同時也將發展一個共乘系統，具體實踐其車群與節能之相關概念與技術。 子計畫二「車載網路之路況資訊服務:設計一個數位交通號誌及安全監測系統」之目的在於建構一個由車載裝置（Onboard Unit, OBU）及道路通訊裝置（Roadside Unit, RSU）所組成的車間通訊系統，提供經由感測單元所偵測及收集的即時地區性的車輛、道路與路況資訊。 子計畫三「車載網路之位置感知服務：設計一個結合汽車及自行車行動導覽遊憩之系統」之目的為在車載網路上提供位置感知服務，並提出自行車智慧型租借營運與自行車觀光導覽兩大研究方向，協助臺灣的公部門與自行車產業界完成「自行車島」的願景，同時與世界綠色思潮接軌。 子計畫四「車載通訊網路繞徑技術」研究車載網路中單播（unicast）之繞徑議題，目的為提出一個在高度動態、時有不連通及密度分佈不均的車載網路中，利用車輛間多重跳躍(Multi-hop)方式，快速且有效的單播繞徑機制。 子計畫五「車載網路之訊息廣播及群播技術」之目的為提供一個有效率且適用於車載網路的群播路由（Multicast Routing）通訊機制，並引入合作式通訊的概念與技術，以提昇網路群播傳輸之可靠度與傳輸效能，同時研究在Selfish車載網路環境下，維持群播效率的方法。 子計畫六「車載網路媒體存取技術」之目標為研發車載網路的媒體存取層的效能改進技術，研究重心將環繞於IEEE 802.11p這個正在制定中的標準，以期能夠在極大化相容於802.11p的同時、改進IEEE 802.11p的效能，以及延伸至對其他基礎網路設備的關鍵合作式通訊技術。 子計畫七「車載網路之同儕式多媒體串流服務」考量車載系統可同時擁有不同無線網路介面的優勢下，設計高效率之同質及異質網路排程機制、探討多媒體串流服務跟網路底層的搭配性，並將同儕網路多媒體串流技術，應用於車載網路之多媒體串流服務系統。

The objective of this project is to establish an advanced Telematics system for safety, energy-conservation, and recreation. Except for considering safety and energy-conservation, we also want to integrate guiding and recreation services on all transportation systems. The Telematics system covers the range from the application layer to the MAC layer. There are two important research topics. One is Telematics services and applications, and the other is Telematics technologies. The objective of the first sub-project is to provide the fleet management services in vehicular networks by designing an energy-conserving and ride-sharing system. By increasing the usage of the roads, we want to achieve the goal of energy-conservation and environmental protection. In the second sub-project, we would like to utilize both on-board unit (OBU) and roadside unit (RSU) to build up a wireless environment for digital traffic sign systems. About wireless networking technologies, we would like to develop a broadcast algorithm, called Streetcast, that is based on the geometric properties of traffic networks. In addition, we will apply network coding to further improve the performance of Streetcast. The objective of the third sub-project is to provide location-based services (LBS) by combining vehicular networks with guiding and recreation for car and bike tours. The first topic is to develop LBS in vehicular networks to provide not only precise location information but also many value-added location-related services. The second topic is to investigate some cases of guiding and recreation for car and bike tours. The goal is to develop a guiding system, which is designed for the purpose of recreation and even energy-conservation, for car and bike tours. Finally, we will implement our system model in Green World in Hsin-chu country, and we will provide cars, bikes, and people location-based and guiding services over vehicular networks. The fourth sub-project focuses on the unicast routing technologies for the advanced Vehicular Ad hoc Networks (VANETs). The VANET is a subclass of MANETs, which would perform crucial functions in road safety, detection of traffic accidents and reduction of traffic congestions. VANETs are evolving as one of the practical applications of MANETs in the future. This vehicular network is interconnected with vehicles which have wireless interface. However, VANETs exhibit very different characteristics from MANETs. The objective of the fifth sub-project is to investigate the broadcast and multicast technologies for VANETs. The relevant technologies of VANETs have attracted numerous research efforts. However, VANETs still lack the concrete and reliable message transmission mechanisms. In this project, we provide various broadcast and multicast mechanisms which are suitable for VANETs. The sixth sub-project is the only subproject which aims at access techniques at the MAC layer for supporting Telematics services and network layer techniques. The wireless vehicular network we consider is a network whose links are physically either 802.11p channels or WiMAX/3G/4G channels. For such a heterogeneous network, we will develop access techniques that help cope with three critical problems in reality. The first problem is topology. To optimize the aggregate coverage with a finite number of RSUs as well as to minimize contention, techniques of topology control and RSU deployment will be developed. The second problem is how to improve transmission efficiency for the vehicles outside RSU coverage. To deal with this problem, we will develop an opportunistic MAC relaying technique that expands the effective RSU coverage. Besides, a mobility management strategy will be designed to minimize the adverse effect due to handoff operations. The third problem is multi-channel operation. A multi-channel allocation technique will be developed to estimate channel delay/quality of a set of heterogeneous channels and allocate idle channels to multiple users with different QoS requirements accordingly. The objective of the seventh sub-project aims at designing an intelligent integrated service system for digital maps and multimedia video/audio applications. Through this service, passengers can enjoy entertainment multimedia services. Our research will focus on satisfying the QoS requirement of the application, improving data delivery rate, and fully utilizing heterogeneous wireless infrastructures.