Research On Resource Management Technology In D2D Communication Network

With the rapid development of science and technology,there are more and more types of intelligent terminal devices,such as smart home appliances,smart phones,wearable devices,etc.,With the rapid development of science and technology,there are more and more types of intelligent terminal devices,such as smart home appliances,smart phones,wearable devices,etc.,and these devices have wireless communication capabilities,and can communicate through Wi-Fi,Bluetooth,cellular networks,and so on.The technology realizes direct communication between terminal devices;in addition,the future network will face the explosive growth of mobile data traffic,the urgent need for a large number of terminal devices,and the shortage of spectrum resources.As D2D(Device-to-Device)communication has the potential to mitigate base station pressure,improve system network performance,reduce end-to-end transmission delay,and improve spectrum efficiency,it becomes a key technology for 5G mobile communication networks.While D2 D communication allows direct communication between neighboring devices to improve network performance,there are many challenges involved in the implementation.On the one hand,in order to improve the user experience,D2 D communication can help the base station to implement service offload and ensure the communication quality of users in cell edge.However,at this time,the base station and other communication devices are still vulnerable to malicious eavesdropping and interference attacks;on the other hand,Considering spectrum efficiency,spectrum utilization can be improved by sharing the spectrum resources of CU(cellular users),at the expense of interference to CU.In order to effectively solve the complex interference problem in D2 D communication network and guarantee CU secure communication,this paper studies the secure communication and interference coordination optimization algorithm for the communication scenario where D2 D and Macro Cell coexist.Firstly,this paper proposes the idea of using D2 D as friendly interference to help CU prevent malicious eavesdropping for the downlink single D2 D secure communication scenario.Furthermore,a power allocation and channel matching optimization algorithm for joint D2 D links and CUs is proposed.D2 D resource management is designed from the perspective of physical layer security.While ensuring the QoS(quality of service)of CUs,D2 D networks can obtain the maximum transmission rate.Due to interference between the D2 D link and the CU and channel matching problems,the network sum rate maximization problem is a difficult nonlinear mixed integer problem.In this paper,the conditions of safety reusing are demonstrated,and the power constraints are transformed,so the original non-convex problem is simplified.Furthermore the optimal power allocation closed solution and optimal channel matching are obtained and the optimal resource management algorithm is designed.The simulation results show that the proposed resource management strategy is better than many existing schemes,achieving the gain of spectrum efficiency and secure communication.Secondly,this paper further studies the downlink multi-channel D2 D security communication problem.Compared with single-channel D2 D,multi-channel D2 D communication can simultaneously reuse multiple CU channels,further improving network spectrum utilization.This paper considers the multi-channel D2 D network utility maximization problem under CU secure communication constraints.Although multi-channel D2 D makes mutual interference more complicated,this paper decomposes the original problem by slackening the channel matching variable and introducing appropriate auxiliary variables,and proposes two D2 D network utility maximization algorithms.The simulation results show that the two algorithms proposed in this paper can obtain the global optimal performance and have significant performance improvement compared with single-channel D2 D communication.Finally,this paper considers the downlink resource sharing problem between multiple CUs and multiple D2 D links,where each D2 D link can reuse multiple CU channels,while each CU channel can also be shared by multiple D2 D links.This scheme can make the most use of spectrum resources,but it is also the most complicated scenario in the D2 D communication network.In addition to the interference between the D2 D link and the CU,there is mutual interference between the D2 D links,resulting in network design.The problem itself is a difficult non-convex problem.Aiming at this problem,this paper proposes two log-approximation algorithms,which can obtain the performance of approximating global optimality,and give its distributed algorithm implementation and proof of convergence.The simulation results show that the proposed two algorithms can fully utilize the local information in the D2 D network and effectively improve the overall network utility.