| With the rapid development of wireless mobile technology, computer technology and Internet technology, especially the wide application of GPRS technology and the release of 3G license, wireless mobile technology is increasingly getting potential markets and becomes possible in railway SCADA system. However, due to the special railway communication structure, it hasn't yet been used massively in railway remote control at home and abroad. Research in remote video supervision based on wireless mobile telecommunication technology has been done in this thesis.Firstly, the development of SCADA system and several popular wireless mobile technologies are introduced. According to the new demands of SCADA system, wireless mobile technology is used in railway remote control and GPRS is used as a typical example in the testing system. In this scheme, one host computer is used as the server, and one laptop as the client, they use GPRS modems to communicate with each other via GPRS networks. How to transmit videos in low bandwidth GPRS networks is very important. Firstly, UDP are used because of the real time character. Secondly, MPEG4 technology and MPEG4 video compression card are use in this plan. Thirdly, For video transmission, the size of the pictures are shortened to make the bit-rate smaller. By these ways and some other effencient ways, the transmission efficiency can be greatly improved. The result of the testing system shows that performances such as system function, real-time, reliability can meet our prospective demands.
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