Investigation And Design Of The Integrated Transmission System For The Railway Emergency Communication

This thesis is devoted to the investigation and design of the integrated transmission system for the railway emergency communication systems. Currently, the railway emergency communication systems rely only on the previous communications systems. Because the bandwidth is limited, it supports a few services, low transmission rate and transmission efficiency. This affects seriously the emergency services operation. Obviously, the problems must be solved to meet the rapidly requirement of the railway transportation, ensure the security, realize the integrated wideband access.Based on the existing railway emergency communications network, service situation and practical requirement, the overall frame of the integrated transmissions systems for the railway emergency communications is proposed. The service and third grade management frame are implemented. Three wideband access schemes of wire, wireless and satellite based are defined in different communication conditions on the operating environment. The design of the access equipments is implemented for the different access schemes. It achieves mainly the functions of collecting, dealing and passing various services.The paper focuses mainly on realizing the real time video exchange between the operating environment and the rescue center by using the video techniques. The design of video-conference system is achieved. The bearing platform of various services of emergency communication is built up, and function designs are finished.According to rapidly development of mobile communications and wireless video techniques, it is carried out that the railway emergency communication will be extended to wireless videoconference systems based on 2.5/3G systems. Finally, the structure and main functions are provided in this thesis.The proposed system is an integrated system. It can realize the integrated services including audio, data, and video. It could satisfy the requirements of the railway emergency for multiple services, and it can be still used for monitoring of the railway station, goods yard, and other industries.