Research On Multicast Transmission In Dense Small Cell Networks

With the rapid development of communication technologies,the types of communication services are more diversified,and the ever-increasing number of terminals and data volumes have placed higher demands on communication performance.Research on the next generation mobile communication technology has been fully carried out.The densely deployed small cell network has become one of the key technologies for improving the system throughput because it can effectively improve the link quality and link rate,increase the multiplexing gain of spectrum resources,increase the access capacity and access rate,and so on.And it has gained extensive attention and research.However,due to the increasing shortage of network bandwidth resources,intensive deployment brings problems such as interference problem,limitation of wireless backhaul resource,and transmission resource.How to utilize limited resources more rationally to meet the growing needs of users and provide better communication services has become an important research direction in the field of mobile communications.As an important part of mobile communication services,multicast services can efficiently serve a large number of users simultaneously.The development of multicast has received more and more extensive attention.This thesis mainly studies the multicast resource allocation and transmission scheme in dense small cell networks.It considers resource limitation and interference problem and proposes a multicast scheduling model with considering limited backhaul resource.It also studies the transmission scheme of multicast video services and proposes an optimized transmission model under resource limitation to maximize system performance and resource efficiency.This thesis first studies the general multicast transmission scheme in dense small cell networks.The goal is to maximize the system throughput while satisfying user requirements.For the interference problem of densely-distributed,the MBSFN technology is first used and small cell base stations use the same resource allocation scheme.An effective multicast transmission scheme is proposed for resource-constrained problem to maximize the system utility and a mathematical model is introduced.In order to reduce the complexity,a multicast resource allocation algorithm based on dynamic programming is proposed,and corresponding improvements are made to the existing signaling interaction flow.Then considering the interference and resource allocation problems in the general scenario,a multicast transmission scheme for cooperation between small cell base stations and resource allocation is proposed.Finally,through the simulation verification of the two schemes,it shows that the two proposed multicast transmission schemes can effectively improve the system performance under the condition of limited resources.In addition,for multimedia multicast services in dense small cell networks,this thesis also proposes a video multicast resource allocation scheme based on SVC coding technology.This solution is mainly based on the SVC video coding technology and uses MBSFN technology to solve the interference problem.A mathematical model is established by considering the limited resources for the encoded video multicast service,and an optimized multicast transmission scheme is designed to provide more targeted and personalized video multicast service to users.Finally,the model is simulated and verified.From the simulation results,we can see that the proposed scheme can further optimize the system performance for resource-constrained video multicast services,and proves the effectiveness of the scheme.