Fuzzy-Based Joint User Association and Resource Allocation in HetNets

In this paper, a user association and bandwidth allocation approach is proposed for heterogeneous networks (HetNets) using fuzzy logic controllers. Due to the heterogeneous nature of user demands, we categorize the incoming mobile users into low, medium, or high based on their data rate requirements. Similarly, the bandwidth utilization in a given small cell base station (SBS) is quantified and evaluated. Based on the peruser demand and bandwidth availability, the controller decides whether a particular user should be associated with that SBS or offloaded to the macro base station (MBS). Moreover, the controller adjusts the fraction of bandwidth allocated to each user based on users data rate requirement and availability of resources towards maximizing the total data rate in the network. The proposed scheme, which is performed by SBSs in a distributed manner, is investigated and compared with two other approaches; namely, the best signal-to-interference-plusnoise ratio (SINR) which is considered as the baseline approach in the literature, and a greedy-based approach where priority in association is given to users demanding higher data rates. Our approach shows promising results regarding the improvement of data rate, bandwidth utilization, and blocking ratio, with an increased number of offloaded users.