为提高视频流在多信道无线多跳网络中的传输质量,提出了一种分布式的跨层优化算法.首先对信道分配、干扰、带宽分配、延时分配和视频传输失真进行了数学建模,然后基于凸规划和拉格朗日对偶分解理论,在视频流端到端延时限制下通过调整信源编码速率、链路带宽、链路平均延时上限及射频和信道分配来最小化总的视频流失真.理论分析和数值仿真表明,所提出的分布式跨层优化算法可以收敛到全局最优解.

In order to improve the transmission quality of video streams in multi-channel wireless multihop networks,a distributed cross-layer optimization algorithm is presented.In this algorithm,first,the channel allocation,interference,bandwidth allocation,delay allocation and video stream distrotion are all modeled.Then,based on the convex programming and the theory of Lagrangian dual decomposition,the total distortion of the video streams under end-to-end delay constraints is minimized by adjusting the source coding rate,the link bandwidth,the upper average link delay and the radio-frequency and channel allocation.Theoretical analyses and numerical simulations show that the proposed distributed algorithm can converge to the global optimum.