Research On Scalable Video Transmission Technology Based On D2D

With the popularity of intelligent terminal devices and multimedia applications,the demand for wireless video services is growing rapidly,and wireless video traffic shows an exponential rise.Complex and diverse terminal devices,heterogeneous transmission channels and fast-growing video traffic bring new challenges for video applications based on wireless network transmission.Using scalable coding technology to transmit video is an effective solution to this challenge.However,the proliferation of users in wireless network makes it difficult for traditional cellular base stations to carry all users' video transmission.As one of the key technologies of 5G communication,D2 D communication technology can reduce the load of base station,improve the capacity of wireless network and increase the number of users' access.In order to cope with the current needs and challenges of wireless video transmission,this thesis has carried out the following aspects of research on the problems of scalable video transmission in cellular D2 D hybrid network.The main contents are as follows:1.Aiming at the problem of resource allocation for real-time transmission of scalable video in a cellular D2 D hybrid network,a joint spectrum sharing and power allocation scheme was proposed to achieve the highest video quality of all users.First,power allocation was performed for each single cellular user and D2 D user according to the transmission rate requirements of each video layer to obtain the optimal video layer combination and power allocation scheme.Then,the suitable spectrum was selected for each D2 D user by using maximum weight bipartite matching method.Therefore,the overall optimal resource allocation could be achieved.Simulation results show that the scheme can significantly improve the video quality gain caused by proper single frequency band multiplexing while ensuring a high access rate for D2 D users.2.In order to improve the transmission performance of scalable video in D2 D multicast network,a scalable video multicast scheme based on user demand perception was proposed.Firstly,the users' interest preference was analyzed by the historical information of watching video.At the same time,the users' willingness to receive video push was obtained by combining video popularity and other information,and the number of multicast cluster receiving users was increased through video push.Then,a cluster head selection algorithm was developed by combining the channel quality and social parameters between users and the users' demand for video quality.Finally,the simulation results show that the proposed scheme can increase the number of multicast cluster users,and meet the different video quality requirements of users.