Research On Radio Resource Allocation Algorithms For D2D Communication In Cellular Networks

In recent years,with the rapid development of the Internet of everything business and the exponential growth of data traffic,the phenomenon of wireless spectrum resource shortage has become increasingly serious.Therefore,scholars proposed to introduce device-to-device(D2D)communication technology in 5G communication to alleviate this phenomenon.The introduction of D2 D communication technology in traditional cellular networks can not only improve spectrum utilization efficiency and system capacity,but also reduce information transmission delay and cell base station load pressure.However,D2 D communication users and cellular users' spectrum resources are shared by using this solution,and they will generate the same frequency interference with each other.If the interference is severe,it will affect the communication quality or result in unavailable communication between them.In order to effectively reduce the co-frequency interference introduced by the D2 D communication technology in the system,and to improve the performance of the cellular network,it is necessary to make a reasonable and effective allocation of communication resources in the system.In this regard,this thesis will focus on the uplink spectrum resource allocation scheme,D2 D user transmit power control and D2 D user mode selection scheme,and explore a reasonable and efficient resource allocation algorithm,so as to reduce the same-frequency interference introduced by D2 D communication technology in cellular networks,and to improve the system spectrum utilization.This thesis mainly studies the user communication resource allocation problem in single-cell hybrid cellular networks.The main research work includes the following three parts:(1)Chapter 3 investigates D2 D communication mode selection and channel allocation algorithm in cellular networks.The algorithm obtains the user's geographic location information in the cellular network to achieve the least interference channel allocation,and then uses the greedy algorithm to select the mode to achieve the same frequency interference between users in the multiplex mode.Simulation results show that the mode selection and channel allocation scheme proposed in this chapter can not only maximize the throughput of the cellular network system but also minimize the co-channel interference.(2)Chapter 4 studies D2 D communication power control algorithm based on harmony search in cellular network.Based on the third chapter,the global adaptive harmony search algorithm is introduced.The new algorithm dynamically adjusts the transmit power of the D2 D sender in the multiplexing mode to reduce co-channel interference and relieve the load pressure on the cell base station.Simulation results show that the joint mode selection,channel allocation,and power control algorithms proposed in this chapter can not only effectively improve the overall throughput of the system but also ensure the communication quality of the system's communication users.(3)Chapter 5 researches D2 D communication resource scheduling algorithm based on improved proportional fairness in cellular networks.In this chapter,the system communication users are divided into scheduling priorities according to the principle of proportional fairness.The priorities are scheduled in order from high to low.This ensures that D2 D communication users with poor channel status are given the opportunity to be scheduled in order to maximize the total system throughput.At the same time,the fairness of the communication users of the system is guaranteed.Simulation results show that the improved proportional fair D2 D communication resource scheduling algorithm proposed in this chapter can achieve a compromise between maximizing system throughput and user scheduling fairness.