| Currently, wireless communication have developed rapidly, mobile users have reached 0.5 billions. The mainly deployed wireless networks consist of GSM, CDMA, Wifi and Bluetooth, which satify the requirements for user mobility and services. Meanwhile, people expect more wirless access technologies with higher rate, larger capacity and wider range, as well as multimedia services with higher bandwidth. Therefore, researching on multimedia communcation in heterogeneous wireless network becomes more urgent.Because wireless networks tend to be heterogeneous, dynamic and limited, while multimedia communication is sensitive to delay, bandwidth, but can be tolerated by people's organs. So we will study the multimedia communication in heterogeneous wirless network from 4 aspects: network organization, transmission scheduling, cache mechanism and commincation protocol.In heterogeneous wirlesss network, all kinds of wireless access technologies vary in cover range, bandwidth, and the nodes always move around, which cause link disruption and heterogeneous bandwidth. Therefore, research on connectivity in heterogeneous wireless network is needed. In the paper, a multi-dimensional self-organization model is proposed to provide stable connectivity for multimedia communication, then relative construct algorithm, maintenance algorithm and routing algorithm are also been discussed. In the model, the wireless measurements are stored distributely as files, which are searched before resource allocation. To promote the efficiency of searching, geography coordinations and realities have been introduced into the model based on CAN. In multi-dimensional self-organization model, logical toplogy matches with physical topology, which decreases network maintenance overhead, reduces measurement report searching time and handover delay, and improves the system connectivity.Except stable connectivity, multi-dimensional self-organization model provides multipath route. Multi-class multi-path collaborative scheduling is presented based on the multipath route, which consist of intra-node queueing, inter-node exclusive transmission and multi-path collaboration. In intra-node queueing algorithm, the transmission data are queued according to their priorities in the node, the data with high priority will be scheduled first. We analyse the relationship between the queue length and queueing delay; in inter-node exclusive transmission scheme, the transimission collision is decreased via token, and the system capacity is promoted; in multi-path collaboration scheduling, a multimedia streaming has been dived into several sub-streamings based on MDC, then transmit the sub-streamings via several paths. The scheme improves the end-to-end bandwidth, reduces the packet loss propability. Even packets were lost, the communication can be kept with low quality.Multi-class multi-path collaborative scheduling provides basic QoS, but the route searching procedure influences on the communication setup time, and network changes influences on end-to-end bandwidth, delay and QoS, which causes communication disruption. Therefore, we propose a hierachical cache mechanism based on MMCS. The mechanism caches routes according to the TTL (Time to live) of the routes, and caches media data in the intermediate nodes of source-destination routes according to end-to-end delay. Before caching, we promote a route convergence and divergence algorithm. Via route and data caching, the start-up delay is reduced, and the QoS becomes more stable.Finally, multi-dimensional self-organization model, multi-class multi-path collaborative scheduling and hierachical cache mechanism are designed into a multimedia communication protocol. The protocol is based on cross-layer and SIP protocol, it modifies the messages and flows of SIP protocol to adapt self-organization and satifies the requirement of multimedia communication in heterogeneous network. Furthermore, we testify the feasibility of the proposed algorithm and protocol via two examples: handover and streaming.
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