Video Transmission Over Multiple CDMA Channels

With the rapid development of mobile and multimedia communication, multimedia services on wireless network have been widely accepted. The 2.5 generation CDMA wireless network has the typical bandwidth of 30~50kbps, which supports low-speed video transmission. Since there is some time to begin operations of 3G networks, how to improve the bandwidth of video transmission and ensure the quality of video streaming is an issue worth studying.This thesis introduces MPEG-4 codec standard, RTP/RTCP and transport of MPEG-4 elementary streams as RTP payload. Then, it proposes a novel packetising algorithm for MPEG-4 video data. This algorithm approves the utilization ratio of the encapsulation and reduces the average error ratio of RTP packet in wireless channel. It improves the overall transmission quality of MPEG-4 video data over wireless channel.This thesis also proposes a framework of video delivering over multiple CDMA channels for expanding bandwidth for video transmission. By bonding the CDMA channels together, the frame rate and picture resolution can be substantial improved. In this framework, an embedded system with cameras and multiple CDMA modules, which is base on ARM processor and Linux, is built for the source. The video is compressed using MPEG-4 and delivered using RTP/RTCP. A novel rate controlling algorithm by controlling the length of buffer list is proposed. An improved RTP translator based on Linux is built as a video server for translating RTP/RTCP packets. This server realizes a novel strategy of combining the RTCP packets to reduce network load. Finally, a client software using Directshow is introduced for selecting and playing streams.