Research On D2D Relay Selection Algorithm In Multi-Scenario

With the continuous development of the innovation business and the sunrise industry of the new century,the 4G communication rate can not meet the market demand.Therefore,whether it is to solve the current communication rate problem or to meet the greater technical challenges in the future,deploying 5G technology is the only way.The D2D(Device-to-Device)technology is one of the 5G core technologies,which allows two devices at close range to be controlled only by the base station and communicate directly without passing through the base station.Therefore,it has a wider communication range,shorter transmission delay and faster transmission rate.Since D2D communication mostly uses the spectrum resources of multiplexed cellular users,D2D has the technical advantage of improving the utilization of wireless spectrum resources,and has been widely studied by scholars.At present,the academic research on D2D relay communication has the same problem:the relay scene is not enough.The multi-scenario means that the relay selection can be divided into two scenarios: social relationship and no social relationship.In D2D relay communication considering the social relationship,there are strong and weak social relationships among users.Without considering the social relationship,there are more and fewer idle users around the D2D source node.The problems of multi-scenario research for D2D relay communication can be subdivided into:(1)There is no better way for most unfamiliar users to participate in relay communication except for incentives for D2D relay communication with weak social relationship.(2)The incentive scheme can stimulate strange users to participate in relay communication,but does not consider whether unfamiliar users trust the relay communication.(3)Scenario with low probability is not considered which is when the idle user density around the D2D sender is small,how to select the relay user becomes a problem.(4)Since the premise of D2D communication can be established is the D2D pair,and incentive programscurrently under study did not take into account the issue of the balance of utility of all parties.In view of the problems existing in the above multiple scenes research,this paper intends to conduct the following research:(1)To solve the problem one,this paper proposes a D2D relay selection algorithm based on cluster network and mobile social network.The precondition for the application of this algorithm is that the D2D pair has a weak social relationship or no social relationship between users,which is closer to real life,and most users around are unfamiliar.(2)In response to the above problem two,three and four,it is proposed to adopt a contract incentive mechanism based on the utility equilibrium solution.Since the D2D relay communication can be seen to some extent as a transaction between a D2D pair,but any transaction requires some form of contract to regulate,motivate and govern.Therefore,on the basis of incentives,the limitation of the contract is used to bring a strong sense of trust to the relay user,thus solving the problem two.In addition,a part of the scheme is the relay communication that introduces the principal-agent theory which targets One-to-One scenario,thus solving the problem three.The program solves the problem four by ensuring fairness by balancing the benefits of both parties.Finally,the paper studies the interference coordination through resource allocation and power control,and uses the LTE-A based D2D communication simulation system to verify the proposed algorithm.The results show that compared with other algorithms,the proposed algorithm has obvious advantages in user signal-to-noise ratio and system throughput.