Spectrum sharing in femtocell based networks using an equal priority power control game

In order to keep pace with the recent proliferation of wireless services and mobile applications, efficient and flexible radio spectrum utilization needs to be ensured in next-generation mobile networks. In this regard, we present a game-Theoretic spectrum-sharing scheme, by considering coexistence of a set of femtocells, belonging to multiple networks, in a coverage area where all cells have an equal priority of accessing the spectrum. We formulate a non-cooperative transmit-power-control game, in which all the femtocells share the spectrum by adjusting their transmit powers according to the interference, until the transmit power is stabilized. We prove that a Nash equilibrium exists for the proposed non-cooperative game, verify that it is unique and highlight the role of specific game parameters in this regard. A novel dual-mode solution is proposed for implementation of the game, which ensures that an equilibrium point can be reached having minimum coordination among the network elements. Finally, we present simulation results to show that the game converges to a Nash equilibrium and provide a throughput performance analysis.