Research On Interference Management In D2D Communication

In recent years,with the rapid development of wireless communication technologies and people's increasing demand for high data rates,high capacity,and green energy,the spectrum resources are becoming increasingly scarce.D2D(Device-to-Device)communication has attracted the attention of researchers due to its advantages of reducing core network traffic load,high data rate,and high system energy efficiency.For D2 D communication the increase of spectral efficiency is achieved through the reuse of cellular user link resources.This communication mode will bring complicated interference problems.Therefore,it is necessary to study the interference management in D2 D communication technologies.This paper separately studies the problem of interference management on two different resource reuse models in a single cell.The main work and results are as follows:1.The one-to-one resource reuse model.First,the communication mode selection scheme based on the user's geographical location and SINR threshold is studied.The interference-restricted area circle and the reusable cellular user resource boundary circle are delimited.Based on this,a communication mode selection scheme for D2 D users is established.Second,the distance-based resource allocation strategy is studied.It is proposed that D2 D users are arranged in descending order of their distance from the base station,and then multiplex sequentially cellular user link resources that are close to the base station,at the same time mode selection is used.This scheme can reduce inter-user interference.Simulation results show that the proposed communication mode selection and resource allocation strategy can improve the maximum throughput of D2 D communication system compared with random multiplexing scheme and each part of the solution.Third,this paper studies the method to balance the throughput of D2 D communication systems and the system energy efficiency.This paper improves the objective function and proposes a non-convex programming problem that reduces the penalties of the transmit power of cellular users and the transmit power of D2 D users,and uses differential evolution algorithm to achieve power optimization.The simulation results show that the transmit power of each user is greatly reduced,and the power consumption and the interference between users are reduced,Moreover the proposed algorithm can achieve almost the system's maximum throughput,while the system energy efficiency is dramatically improved.2.The many-to-one resource reuse model.First,the many-to-one resource reuse model is established as a many-to-one matching problem with peer effects.The initial matching process and the exchange operation process in the existing matching algorithm are improved.The blocking pair with the largest increase in throughput is eliminated successively,and a resource allocation strategy for guaranteeing the quality of service of the user is obtained.According to the simulation analysis,the proposed resource allocation strategy not only obtains a stable resource allocation scheme,but also improves the system throughput.Second,this paper studies the method of controlling the transmission power by using differential evolution algorithm to balance the throughput of D2 D communication system and the system energy efficiency.Strong transmitting power of D2 D users can bring relatively high communication rates,but at the same time it brings strong interference and may reduce energy efficiency.In order to solve this problem,a new objective function is given,and a non-convex programming problem that can reduce the D2 D user transmitting power penalty term is proposed,and then a differential evolution algorithm is used to optimize the power control process.The simulation results show that the system energy efficiency can be greatly improved while achieving close to the maximum throughput of the system.