Design And Implementation Of Embedded Multimedia Terminal Based On WLAN

Unlike cellular communication networks, wireless local area network (WLAN) can be built up and updated easily, it's widely used and low-cost. It is reasonable for portable devices to access through WLAN rather than cellular systems in some situations.In this thesis, a design scheme for a portable multimedia terminal for personal communication based on WLAN is proposed. It can be used to fulfill real time communication wirelessly at home or in offices or even outdoors and process multimedia signals combined with audio, video and data.A two-core structure based on ARM and DSP is adopted, which make it easier to process multimedia data and intercommunicate through network, and more flexible to expand the system capability and update the software.The Linux OS is ported to embedded system, which is responsible for controlling the system and providing interactive interface and friendly GUI; a video encoder complied with H.264 standard for real time video compressing are implemented on DSP; the compressed data are transmitted over WLAN based on streaming media technique, using open standard protocols (RTP/RTCP, RTSP).To accomplish the scheme, the optimizations for H.264 encoder are carried out on DM642 DSP platform, the Linux device drivers and RTSP servers & clients for H.264 streaming are programmed respectively, and so on. It is capable of multimedia signal collection, processing and transmission on live.