The Development Of Wireless Video Surveillance Terminal Based On 3G Network

Video surveillance technology is a synthesis technology composed of computer technology, network technology and multimedia technology, which is applied widely in industry, traffic, electric power and intelligent office building etc. With its convenient, intuitive and content-rich features, Video surveillance technology has become an important means of modern management and detection.The video surveillance system based on the emerging networks and embedded technology has characteristics of small size, low cost, high stability and real-time, compared with the traditional surveillance systems.3G standard is put into use in China now. Thanks to its powerful function of wireless data transfer, the 3G based wireless video surveillance system can overcome the problems caused by geographical location, wiring costs and remote surveillance, which will bring a revolution on surveillance technology.The paper brings forward and designs an embedded network video surveillance terminal based on 3G communicaton technology and digital video encoding technology. The video surveillance terminal can capture the video signal from camera and compress it; Then the compressed data is transmitted through the 3G wireless network to the base station; The base station then sent the data to the monitor center via internet according to the IP address included in the data packet, where the compressed video data was decoded and displayed.The main work of this paper:(1) The paper gives the hardware framework of the system and brings forward a method to design HPI interface circuit between ARM and DSP. Besides, this thesis ananlyzes the software architecture and explores the design of application program based on V4L.(2) This paper carried out in-depth analysis and research on the network transmission process from the physical layer to application layer, including the driver design of Wireless access Module, the application of PPP protocol in data link layer, the encapsulation of UDP/IP protocol and the modification to RTP protocol.(3) Video picture has a lot of information, and wireless telecommunication system has some drawbacks such as small bandwidth, bad performance in resisting the interference, the severe fading, and the high error rate. This paper brings forward an adaptive flow control algorithm in order to improve image quality under the premise of smooth playback in real time.