Ad Hoc网络中多点对点视频传输系统设计与仿真

Design and simulation of multipoint-to-point video transmission system over Ad Hoc networks

针对传统C／S（client／server）结构的流媒体模式存在服务器负载较大问题，设计了Ad Hoc网络中多点对点视频传输系统．发送端依据路由应答分组（RREP）选择优先权高且路径最短的路由来传输视频．与协议扩展前相比较，可用路由的节点不再集中在接收端附近，故当发送端附近的某个链路断开时，视频信号仍可以由其他链路来传输．从仿真结果可以看出：使用扩展动态源路由协议时，系统的归一化路由开销增加了0．02～0．08，但是从平均峰值信噪比和视频中断发生时间长短与次数等方面来看，视频的传输品质有显著提高，其中以3个传输点的效果最佳．

A multipoint-to-point video transmission system over mobile Ad Hoc networks is designed to solve the problem that the server load is very heavy at the conventional C/S （client/server） configuration of the streaming media mode. The sender chooses the shortest high priority route to transmit the video based on the route reply packet （RREP）. Compared with the original dynamic source routing （DSR） protocol, most of the route nodes no longer distribute around the receiver, the video can still be transmitted by other link when a link breaks nearby the sender. The simulation shows that the system which uses the extended DSR protocol increases the normalized routing load between 0. 02 and 0.08. However, the quality of video streaming transmission is enhanced greatly in the average peak signal to noise ratio （APSNR） and the length and number of interruptions, especially under the status of three transmission points.