Research On Relay Selection In D2D And Cellular Hybrid Network Multicast Conmmunication

With the development of mobile communication technology, the demand of sharing wireless data is growing, which puts forward higher requirements to the service flexibility and coverage area of IMT Advanced of system, what is more, the cellular communication system, which shares the data based on the center of the base station, has certain limitations especially on the development of the local business. D2D (Device-to-Device) communication technology, which means that the users close in space can directly communicate with each other without data forwarding through the base station, can obtain better local user experience and higher data transfer rate.The D2D technology is introduced into the traditional multicast service, which can expand the range of multicast service, reduce multicast resources consumption, and increase the efficiency of the multicast service. The research background of this paper is based on the cellular and D2D hybrid network. In this paper, we briefly introduces the D2D communication model and the process of connection, setting up and release, then the interference during the process of the D2D communication is analyzed in different resource reuse mode, and the D2D technology in the application of multicast is also described briefly. The D2D dynamic clustering schemes in multicast communication are put forward in this paper with minimal resource consumption, minimum power and minimum interference as optimization objectives respectively. Finally, multicast relay selection scheme of the cellular and D2D hybrid network is put forward based on the comparison of utility values.Firstly, this paper puts forward a dynamic clustering scheme of the D2D assisted multicast communication. In the D2D assisted multicast communication, the scheme can select different clustering algorithms to achieve the maximization of network utility value according to the load of network. The clustering algorithms are divided into three types:the minimum resource consumption algorithm, the minimum power algorithm and the minimum interference algorithm, which can be adaptively selected according to the state of the network load. Simulation results show that the dynamic clustering scheme can be applied in cellular and D2D hybrid network multicast transmission services to increase the network multicast transmission utility value, reduce the terminal energy and the interference to the base station, and save the spectrum resources.Secondly, a multicast relay selection algorithm is introduced in the D2D and cellular hybrid network based on the comparison of the utility value. The optimal transmission strategy is chosen by comparing utility values of the fixed relay assisted multicast and D2D assisted multicast to improve the overall utility value of the cellular system. By effectively combining the advantages of two kinds of cooperative relay multicast, selecting the best relaying mode, the transmission rate of multicast service and the coverage to edge users are improved, therefore the overall utility of cellular systems is optimized.