Reaserch On Scalable Video Multicast Based On D2D Multicast Underlaying Social-Aware Cellular Networks

With the popularity of terminal devices and video applications,the demand for wireless video services of terminal users continues to grow,and mobile video traffic has grown exponentially.Heterogeneous transport channels and diverse terminal devices put forward higher requirements for traditional video transmission.Scalable video multicast technology is an effective solution,and next generation wireless communication networks support multicast transmission of base stations.However,the number of terminal users in the network has soared,and the traditional cellular network cannot carry the video transmission of all terminal users.The D2D(Device-to-Device)multicast communication technology provides a new idea for improving the user access rate of the network.The D2 D multicast technology is a combination of D2 D communication and multicast communication,which enables multiple neighboring users to transport the same video data directly without accessing the base station.However,in the actual communication scenario,in addition to the physical distance between the users,there is also social relationship,which makes the formation of the D2 D multicast link more complicated.Because of the problem of scalable video multicast transmission in traditional cellular networks,this paper adds D2 D multicast communication to social-aware cellular networks and proposes a two-stage scalable video multicast transmission scheme.Comprehensively utilize the user's social and physical attributes to form effective D2 D multicast clusters through a greedy iterative algorithm.In order to solve the channel resource allocation problem and interference management problem brought by D2 D users' access,this paper proposes a joint optimization algorithm aiming at maximizing the video transmission throughput of D2 D users.The algorithm uses the geometric programming method to calculate the optimal power allocation,and then uses the bipartite graph matching algorithm to select the reusable cellular uplink channel for each D2 D multicast group.The simulation results show that the effects of physical distance threshold and social relationship threshold on system performance.Compared with the strategy of adding D2 D unicast communication,the simulation results show that this strategy has significant gains in D2 D user access rate and video transmission throughput.This paper also proposes a single video stream multicast transmission resource allocation optimization algorithm to maximize the overall utility value of the system.The algorithm takes the D2 D users and the cellular users as a whole,and uses the recursive algorithm to analyze the resource allocation process from top to bottom.Compared with the traditional cellular network and the scalable video multicast strategy in the social-aware cellular network scenario with D2 D unicast communication,this strategy can make more efficient use of uplink spectrum resources,increase the number of accessed users and improve the average received video quality of users.