The Design And Realization Of Communication Administration Module Of Expressway Supervisory Control System

With the domestic traffic and transportation constructions mushrooming, Expressway Traffic Supervisory Control System (ETSCS) has become an investment hotspot in expressway constructions. As an up-to-date new technology in the domain of transportation, ITS is extending -its scopes and functions. Communication Administration Module (CAM) is one of the elemental ingredients of ITS. It is the basal pursuit that supports traffic administration and control, traffic and transportation planning, ITS implementation, and research of traffic flow theory as well. Via real-time and reliable traffic data acquisition and processing, we can discern traffic status, and define the properties of traffic problems so as to provide a basis to implementing information service subsystem of ITS. Research and developed production of software in the field of traffic supervisory control shall have extensive application outlook, together with tremendous social and economic benefit. This thesis, which Lakes expressway traffic supervisory control as its background, researches and analyzes a relatively advanced designing scheme of Expressway Supervisory Control Center System (SCCS). And thus the author launches on a discussion on the CAM communication linking design in this SCCS, and demonstrates the research and realization of the CAM. This paper brings forth a new fashioned, efficient, reliable and real-time scheme of data acquisition and processing. The author gives a discussion on the material realization of the key techniques applied in the scheme too.The research and design of this subject synthesizes multifold technologies, which arc digital communication, network, OOP (Object Oriented Programming), and DBM (Data Base Management). This paper starts with the analysis of ETSCS's structure and tasks characteristics. With that and based on OAN (Optical Access Network), this paper discusses a design of the communication linking between CAM and its outstations' devices. The author then gives a analysisof the real-time performance, expansionary capability and reliability of the de.sign. Secondly, the author analyzes the software system' s designing idea and modules assignment in the SCCS. Subsequently, this paper introduces the function mechanism and features of the software system. In the part of CAM software developing research, this paper gives an analysis and research of the CAM's real-time tasks and communication requirements. Thereafter a settlement of real-time communication is given. The applications of some key techniques in software developing,.such as multi-serial port and multithreading are also expatiated and investigated. Finally, in the part of the software material designing and realization, the author presents the proceeding flow chart and function modules of the software. At the end of this part, major function modules and its program codes, together with some of the HMI (Human Machine Interface) forms are introduced, whereupon the CAM is realized.