Research On Resource Allocation In In-band Full-duplex OFDMA Networks

The external contradiction between the shortage of spectrum resources and the explosive growth of wireless communication service drives the inner change in wireless communication theory and technology.Thus,to improve spectrum utilization efficiency of FDD and TDD and eliminate the differences with respect to the manner of spectrum resource use and management are one of the goals of the future mobile communication technology innovation.In-Band Full-Duplex(IBFD)wireless communication system has been recognized as an attractive option for it allows a wireless terminal to transmit and receive simultaneously in the same frequency band.The In-Band full-duplex OFDMA network can provide relatively high spectrum utilization efficiency,and the effective resource allocation scheme can further improve the network performance.In this thesis,two kinds of resource allocation algorithms for in-band full-duplex OFDMA networks are proposed to solve the problems of carrier and power allocation in the networks.On the one hand,an optimization problem of subcarrier and power allocation is proposed to maximize the network transmission rate for OFDMA networks where the base station and the user perform in-band full-duplex bidirectional transmission on the same subcarrier.Under the constraint condition,the Lagrangian multiplier method and the KKT condition are used to obtain the necessary condition for the optimal solution of the problem.According to the necessary conditions of optimization problem,a subcarrier and power combining algorithm is proposed.The algorithm is divided into three steps.Firstly,the power transmission rate is assigned to each user in advance by using the power water-filling algorithm.Then,the subcarrier is allocated by the Hungarian algorithm with the estimated rate.Finally,based on the results of subcarrier allocation,the power water-filling algorithm is used to allocate the power to maximize the transmission rate.The simulation results show that compared with the JSAPA algorithm,the subcarrier and power combining algorithm proposed in this paper is more efficient,and the fairness among users is better.On the other hand,in three-node full-duplex communication OFDMA network,where a pair of uplink and downlink users and base stations transmit in the same subcarrier,inter-node interference is also a need to consider the issue in addition to residual self-interference.In this thesis,a three-dimensional matching is proposed to solve the problem of user matching and subcarrier allocation in this network.At thesame time,for the constraint of uplink transmission rate,a power allocation method is proposed to reduce the influence of self-interference on system performance.This thesis also analyzes the convergence and complexity of this algorithm,and compares the network performance with the exhaustive algorithm and the random algorithm.The simulation results show that proposed algorithm is close to the performance of the optimal algorithm,and the complexity of the algorithm is low.Proposed algorithm not only can solve the uplink and downlink user matching and subcarrier allocation problem,but also use the power allocation to satisfy the uplink transmission rate constraint.Finally,the thesis summarizes the research contents of the full-duplex full-duplex OFDMA network resource allocation and the shortcomings of this paper.The future research direction of full-duplex wireless communication is be briefly stated at the end of this thesis.