Competition in femtocell networks: Strategic access policies in the uplink

Ali Khanafer (1) , Walid Saad (2) , Tamer Başar (1) , Mérouane Debbah (3)

1 CSL - Coordinated Science Libratory [University of Illinois]
2 University of Miami
3 Chaire Radio Flexible - Chaire Radio Flexible Alcatel-Lucent/Supélec

In emerging small cell wireless, each femtocell access point (FAP) can either service its home subscribers exclusively (i.e., closed access) or open its access to accommodate a number of macrocell users so as to reduce cross-tier interference. In this paper, we propose a game-theoretic framework that enables the FAPs to strategically decide on their uplink access policy. We formulate a noncooperative game in which the FAPs are the players that want to strategically decide on whether to use a closed or an open access policy in order to maximize the performance of their registered users. Each FAP aims at optimizing the tradeoff between reducing cross-tier interference, by admitting macrocell users, and the associated cost in terms of allocated resources. Using novel analytical techniques, we show that the game always admits a pure strategy Nash equilibrium, despite the discontinuities in the utility functions. Further, we propose a distributed algorithm that can be adopted by the FAPs to reach their equilibrium access policies. Simulation results show that the proposed algorithm provides an improvement of 85.4% relative to an optimized open access scheme in the average worst-case FAP utility.

Domains: Networking and Internet Architecture [cs.NI]; Computer Science and Game Theory [cs.GT]

Ali Khanafer, Walid Saad, Tamer Başar, Mérouane Debbah. Competition in femtocell networks: Strategic access policies in the uplink. IEEE ICC 2012, Jun 2012, Ottawa, Canada. pp.5070 - 5074, ⟨10.1109/ICC.2012.6364563⟩. ⟨hal-00769468⟩