Cooperative Multicasting for Wireless Scalable Video Transmissions

Cooperative multicasting is a promising technique to combat severe fading and path loss for wireless video delivery. In typical wireless video multicasting, nodes under the worst channel condition determine the video delivery quality, thereby limiting the system performance and affecting the Quality of Experience (QoE) of the users. Existing cooperative multicast schemes may not fully exploit the characteristics of scalable video over wireless networks. To tackle this problem, we propose two new cooperative multicast schemes called OppCM and CodedCM for scalable video delivery. OppCM performs opportunistic listening and conditional demodulating to enhance the system performance; CodedCM delivers layer-encoded video with multi-resolution modulation through cooperative multicasting. We analyze the system performance in terms of average outage probability for four cooperative multicast schemes, including direct multicast (for baseline comparison), pure cooperative multicasting, and the two proposed schemes OppCM and CodedCM. We also evaluate their performance via simulations. The results show that the proposed OppCM and CodedCM outperform the other two schemes, demonstrating that they are indeed promising solutions to wireless scalable video multicasting.