Design Of Wireless Video Transmission System Based On 802.11

With the rapid development of the wireless communication technology and the computer network technology, the bandwidth of wireless network has been improved, and the real-time data transmission ability of wireless network is aiso being enhanced continuously. Also with the popularization of the Wireless LAN(WLAN), the video transmission technology based on WLAN has become the research hotspot. Compared with the wired network, wireless network has many advantages such as flexible network structure, good expansibility and portability, convenient network reconstruct, low maintenance cost, etc.In this paper, the design and realization of a real-time wireless video transmission system based on embedded Linux OS and S3C2440A microprocessor which uses an embedded ARM920T kernel is presented. The system can transmit video images compressed by MPEG-4 compression encoding software to the video server where the video image be analysed, stored and displayed via 802.11 wireless network.Firstly, the overall design of the system, including the hardware design and the establishment of the software development environment, is presented. Among them, building of the cross-compiling environment is the basis of the completion of the follow-up development work. The transplantation of Qt creates the conditions for application softwarerunning. Then the design and implementation of the main function modules of the system are introduced.The main function modules include the video data capture module, the hardware of the wireless video transmission module, the transplantation of the embedded Linux drivers, the MPEG-4 digital video compression software and the application software The user datagram protocol(UDP) and real-time transport protocol/real-time transport control protocol(RTP/RTCP) are applied in the system to implement video transmissions in 802.11 WLAN. The system can achieve high reliability and convenient usage. It can be easily applied to the video transmission occasions such as wireless video surveillance, wireless video conference which based on wireless video.