| Rapid economic growth, vehicle possession increase, and traffic congestion result in serious "city problems". City traffic is vital in urban economic activities, and become a focus of solving congestion worldwide. In recent years, ITS, in light with user-vehicle-road dynamic relation, based on travelers'data, to some extent releases the problem of traffic congestion by improving road utility and traffic flow, lowering the rate of traffic congestion and accidents, reducing the delays caused by congestion and accidents, as well as guiding scientifically. Traffic information is the key source for functions of traffic management, traffic control, traffic guidance, and traffic information service. It provides foundation for scientific traffic management and planning. Therefore, comprehensive, reliable, accurate and timely traffic information collection directly affects the results of management and control in road transportation system.Based on current traffic information collection techniques of magnetic frequency, wave frequency, video frequency and GPRS/CDMA, some of the traffic problems can be solved when real traffic parameters are obtained. While restricted by surroundings and approached of information collection, only part of the entire information is available. Demand can not be met if macro transport situation or real micro individual travelers are required to describe. IPv6 network, which gradually replaces digital radiocasting, telecommunications and network, serves as data collection condition. It satisfies all the requirements for real data collection of all vehicles, with the merits of mega-spatial, guaranteed, mobile, and highly efficient QoS features.The paper is based on the Plans for National Key Rudimental Research Developments (Project 973)--"Optimal organization and control in city traffic system" in the Program of "Research on the fundamental scientific issue of urban traffic bottleneck", and the Plans for Jilin Province Scientific and Technological Development-"Framework research by mobile IPv6 orientation". Tentative research is made on the network construction and management concept of future intelligent transport. The research of the thesis is on two presuppositions. First, it is established on the foundation of overall static transport information database, including GIS, vehicle information database and pedestrian information database. City residents'life is entirely digitalized. Second, transport communications network is consummated and vehicles are installed vehicle-carried units for information collection and mobile communication.The system framework of comprehensive transport information collection and procession was first raised in light of IPv6 in the thesis. It is composed of three layers for collecting, transmitting and storing ITS information, i.e., mobile input interface, public transmission, and control center. Vehicle-carried data collection units collect information of GPS data, and vehicle meter data read by sensors. These data are about the running direction and speed, and travelers' ID as well. The data are packed in IPv6 data package, and reported to the control center through high speed transmission network, which adopts light-fiber transmission and long distance wireless transmission 802.16e protocol. To avoid network jam in rush hour of vehicle data collection and report, we design the comparatively stable and rapid vehicle-carried network in accordance with vehicle conditions, communications, and accreditation. The adoption of 802.11g protocol makes multi-way transmission to reduce the requirement and congestion of wireless data channel. Real and stable transmission of collected data is guaranteed. Control center processes the collected data to make real traffic management and control, and to analyze issues of transport safety, trip distribution and urban land allocation. It is also accountable for the core functions of management, data archive and broadcast for transport network AAA.When vehicles run, continuous contacts are conducted within the domains in the network. Improper switches will block the contacts. The introduction of AAA system into transport network running and management may fasten the speed of ascertain and authority in adjacent domains, and formulate transport fee-levy models based on real time consuming data. Through the real time functions of ascertain, authority and record, dynamic management approach of intelligent transport network is realized base on AAA. Network continuity and rational allocation of transport resources are guaranteed when vehicles run past different domains.At the premise of real and continuous transport information network, the features of traffic flow are defined.Based on marginal tag method and matrices theory, the natural features of macro road network and blocks, as well as the social features of nodes are defined. Real road network is abstracted into mathematic models to actualize the transformation of matrix, real road network, and abstract network. After analysis on macro road network and blocks, the idea of block is stressed on to analyze its spatial, adjacent, vehicle existing, and temporal-spatial restriction features. Temporal-spatial coordination models are formulated among pedestrians, vehicles, phases, micro block, route, nodes and environment.When the UniqueID is joined with reports of vehicles' natural data and their positions, numerous data are collected, considering the properties of vehicles'existence in the block. Flow, speed and density, three key parameters of traffic flow, are obtained, especially variable speed and density that can hardly gathered by other means. OD matrices are formulated to get the probabilities of route selection, single vehicle turning, and volume of public transport passengers.Simulation tests prove that data collection network effectively tackles network congestion, guarantees system transmission. AAA system makes real time dynamic management on vehicles. Coordination of pedestrian-vehicle-road-environment is expressed by vehicle positioning models. Three levels are achieved to lay foundation for intelligent transport control, guide and safety that micro vehicle real time data are collected and tracked; flow, density and speed are obtained; real time data and traffic flow parameters in macro road network are found.
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