Research On D2D AD-HOC Network Broadcast And Unicast Scheduling Technology

Nowadays,with the extending scale of mobile subscribers and high demand in aspect of data communications all around the world,there has been a continuously increasing pressure on cellular networks.In order to overcome and enhance the performance of the communication network,the fifth generation of mobile communication technology(5G)is planning to be deployed.As one of the key technologies of the fifth generation of mobile communications,Device-to-Device Communication(D2D)technology proposed by 3GPP is able to significantly improve the utilization of the system spectrum and reduce the system load to some extent.Therefore,it mitigates the lack of existing mobile resources,which triggers widespread attention in a certain area.At present,3GPP’s the main research focuses on D2D broadcast technology standardization.And about D2D unicast,academic research concentrates on pure algorithms such as resource allocation,interference avoidance and so on.In other words,it lacks a comprehensive analyze to combine the advantages together of both D2D broadcast and unicast,and then design joint scheduling algorithm.In response to this situation,this paper compares the performance between broadcast and unicast in D2D ad hoc networks,and introduces a set of optimization schemes that can increase the system throughput and improve the overhead.The main work and contribution of this report are as follows:In the D2D broadcast transmission,the spatial Poisson Point Process theory is used to make mathematical modeling and performance derivation about the D2D ad-hoc network system based on the Sidelink frame structure in 3GPP D2D protocols.Through the restrictions of the distance and the number of users,the paper analyzes the performance of D2D broadcast system.In the D2D unicast transmission,the paper designed and presented the competition mechanism of the four-way-handshake.The paper consists of steps of resource request,resource feedback and resource determination to form a complete process of resource allocation and accomplished the radio resource management functions such as time-frequency resources,transmission power and modulation coding(MCS)needed for D2D unicast transmission.Then it analyzes the performance of D2D unicast transmission.Finally,the paper compared and anslyzed simulation results and performances of D2D broadcast and unicast.The joint system is designed to allocate resource of D2D unicast and broadcast using frequency division method.By comparing the results of joint system and single system,the set of joint system is feasible and has more performance advantages.