AN INTERFERENCE MITIGATION TECHNIQUE FOR DEVICE-TO-DEVICE COMMUNICATION NETWORKS BASED ON USER DISTRIBUTION

Abstract

Device-to-Device (D2D) communication is one of the enabled technologies in Fifth Generation of cellular networks that allows two devices in close range to communicate without traversing the Base Station (BS). Device-to-Device Communication comes with numerous benefits which include data traffic offloading, location awareness service, social networking and smart city. However, this D2D Communication Network comes with several challenges such as Interference Management which causes great impairment to communication. Therefore, to improve the D2D Communication performances and maximize its potentials, interference must be reduced to reduce this issue of interference, several researchers’ proposed different approaches to mitigate it and soft frequency reuse (SFR) through fair bandwidth allocation has been greatly explored. SFR scheme, the users in the cellular network are divided into two; the Center Users and Edge Users. In this research work, three different algorithms for bandwidth allocation namely; separate bandwidth allocation; overlapping bandwidth allocation and hybrid bandwidth allocation were developed for three categories of users in order to mitigate the interference between the Cellular Network and Device-to-Device Communication Network. The bandwidth allocation is done in fairness among the center users, edge users and the Device-to-Device users based on Users demand in each network in order to reduce interference. The users in the network are randomly selected. The proposed algorithms were evaluated by simulation using MATLAB in terms of Signal-to-interference plus noise ratio (SINR) and system capacity. The results of this research work are presented by comparing the performance for different number of D2D users in the network. Hence, evaluation of how the size of D2D networks can affect the cellular network performance was done as the first unique contribution. For the two proposed algorithms (Separate bandwidth allocation and Overlapping bandwidth allocation), comparison was made with fixed bandwidth allocation. When the number of D2D users is within 10% , the Hybrid bandwidth allocation and Separate bandwidth allocation for three cases (the high, average and low edge users) outperforms others for D2D Users SINR with the improvement up to 34% but when the number D2D users increases to over 30% in the network the performance reduces to 27%. Therefore, as the number of D2D user increases in the network, the performance of the system reduces. For future research, the algorithm can be improved upon to accommodate more D2D users.