Research On Coexistence Of LAA And Wi-Fi In Unlicensed Band

Extending LTE to the unlicensed band has become a new direction for academia and industry to address the 1000-fold challenge of data traffic,LAA as a global solution proposed by the 3GPP has been the concern of all walks of life.However,deploying LAA directly can have.a serious impact on the performance of Wi-Fi systems.Therefore,the design of fair coexistence access mechanisms is a problem that LAA needs to solve first when it is widely used.Based on this,this paper mainly studies LAA co-existence access mechanism in licensed spectrum with Wi-Fi,and focuses on both fairness and effectiveness.In terms of fairness,in LAA dense deployment case,the performance of Wi-Fi systems will drastically deteriorate due to the high collision probability,which in turn affects the fairness of Wi-Fi and a LAA channel access mechanism based on alliance game mechanism is proposed.In the proposed channel access mechanism,we first form LAA BSs into clusters in which BSs access the channel as an entity using LBT mechanism.Thereby effectively reducing the collision probability and ensuring the performance of the Wi-Fi system.At the same time,a low-complexity clustering algorithm is also designed.The simulation results verify that the fairness of the mechanism and the algorithm.In the aspect of validity,a joint sub-channel and power allocation algorithm based on D.C.programming is proposed for the problem of serious intra-cluster interference in the proposed access mechanism.Based on this,we model the resource allocation as a mixed integer nolinearprogramming,and later the problem is transformed into D.C.programming and an iterative joint subchannel and power allocation algorithm is proposed.Simulation results verify the effectiveness of the algorithm.