Research On Wireless Video Stream Transmission Based On Network Coding And Cooperative Diversity

With the development of society and economy,the network technology has penetrated into all aspects of people's work and life.At the same time,people begin to have higher and higher demand on the stability and timeliness of the network.In particular,with the popularity of wireless intelligent terminals,wireless video traffic is greatly increased,especially in the field of battlefield and emergency communication.The video stream is affected by bandwidth,noise,packet delay,bit error and packet loss in wireless communication networks.In order to overcome these problems,it is necessary to design a stable and reliable video stream transmission scheme.In the traditional network transmission mode,the relay node only has a single routing function,that is,store and forward.On the basis of the network coding technology,the coding function is added to the relay nodes,which can encode the information of multiple links and then forward to the next node.So the network coding technology can improve the link transmission capacity and enhance the stability and robustness of the network.The cooperative diversity technology allows multiple wireless mobile terminals as relay nodes each other to form a virtual antenna array.It can stand against multipath fading and path loss in the wireless channel,improve the transmission quality of the network,and improve the system reliability of transmission.In this paper,we propose a cooperative diversity transmission scheme based on random linear network coding(RLNC)for the wireless video stream transmission,which integrates RLNC and cooperative diversity.At the same time,we establish an optimization model,and propose a cooperative mode switch algorithm,which can minimize the cost of proposed transmission scheme.According to the quality of service(QoS)requirements of wireless video stream,the experimental results show that the proposed scheme decreases packet error rate(PER)and end-to-end delay significantly in the process of wireless video stream transmission.This design scheme improves the reliability and real-time performance of wireless video stream transmission.