College Admission Game with Transfers for UL Small Cell Communication

Abstract

Next-generation cellular systems are expected to rely on the viral and dense deployment of small cell base stations. In this chapter, we study the problem of UL user association in such dense small cell networks. In particular, in a small cell network, cell association involves interactions between three key types of devices: users, small cell base stations, and macro-cell base stations. These devices will often have conflicting objectives that must be considered during small cell association. We show that the problem can be effectively formulated as a college admissions game with transfers in which a number of colleges, i.e., small cell and macro-cell stations seek to recruit a number of students, i.e., users. In this game, the users and access points (small cells and macro-cells) rank one another based on preference functions that capture the users’ need to optimize their utilities. These utilities are defined as a function of the packet success rate (PSR) and delay as well as the small cells’ incentive to extend the macro-cell coverage (e.g., via cell biasing/range expansion) while maintaining the users’ QoS. We then design a distributed algorithm that combines notions from matching theory and coalitional game theory to solve the game. Simulation results show that the investigated approach yields a performance improvement, in terms of the average utility per user, reaching up to 23% relative to a conventional cell association algorithm.