关键词: 自适应速率调节，无线流媒体传输性能，跨层设计

Abstract: Real-time media streaming over wireless mobile ad hoc networks (MANETs) has been an active area of research in the last few years. However, real-time multimedia delivery in such wireless environments identifies significant challenges due to both the strict QoS requirement of multimedia applications and the dynamic characteristics of wireless mobile networks. This paper proposed an adaptive rate adjustment mechanism for real-time media streaming over MANETs, i. e. ARAM. This mechanism, based on the cross-layer design, predicts the network condition according to the GM (1，1) model. On the other hand, the transmission rate is adaptively adjusted according to the predicted bandwidth and queue length. In order to evaluate the ARAM performance, we generated a set of video streams using NS2 simulation for typical network scenarios. Our statistical and mathematical analysis demonstrated that the ARAM improves the reliability of real-time multimedia delivery significantly, and provides soft QoS guarantees as well.

Key words: Adaptive rate adjustment, Real-time streaming performance, Cross layer design