Cross-Layer Optimization for Packetized Video Communications over Wireless Mesh Networks

In this paper we propose a cross-layer optimized framework which jointly considers the video coding and transmission in wireless mesh networks. In our framework, video coding parameters, network path selection, MAC layer frame size, and modulation and coding schemes at PHY layer are systematically optimized across the entire network protocol stack. To achieve the goal of real-time video communication with high-quality and/or stringent delay requirements, the proposed framework is formulated into a minimum distortion and/or minimum delay problem. The formulated problem is efficiently solved as a Lagrange dual problem, and the solution is tested by H.264/AVC. The system performance in terms of the perceived video quality is compared between the cross-layer optimized system and the current system. Experimental results indicate the effectiveness and efficiency of the proposed optimization framework.