Video Emergency Telephone Based On Self-Heal Ring

When it come to a new century, the construction of expressway expands rapidly. As a tool of emergency call on the expressway, emergency telephone is becoming more and more important. In the moment when the nation strength the management of the expressway, video emergency telephone emerges as the times require. Emergency call is the device which is built on the either side of the expressway to pick up the call for help of bus drivers. Besides the elementary function, it can monitor the whole expressway. It will help the control of expressway, and has a wide future. By analyzing the shortcomings of current emergency telephone system, a new method is presented based on self-healing ring. The key technique of this method and the way to realize hardware and software is described. The paper is organized as follows:First of all, I introduce the development of ET(emergency telephone) and analyze the advantages and disadvantages of current ET systems. The necessity of video ET is also provided.Second, I summarize the key technique of establishing this system, including self-heal ring, WDM, serial communication, data accessing, video compress and Visual Basic 6.0.Third, according to the features of the system, I bring forward the whole project in software and hardware. The Requirement Analysis and the design of database is included.Then I divide the software into several parts: loading, calling, self-check, video processing, and describe the function and realization of each subsystem.The last section is the sum-up of the paper. I point out the bugs of system and the mending. Also I prospect the wonderful future of video ET.