Optimal and Heuristic Decision Strategies for Load Balancing and User Association on HetNets

User association and load balancing are among the main challenges in designing Heterogeneous Networks (HetNets). Both problems are highly interdependent and have direct effect on the user experience and satisfaction. In this work, we model the user association problem as an integer linear programming (ILP) problem aiming to balance the traffic among macro and small cells. In addition, we introduce two heuristics: a centralized solution based on a greedy algorithm and a distributed probabilistic load-aware solution. Our solutions produce better results in terms of the number of accepted users and load balancing than some of the main strategies proposed in the literature.