Game Theoretic Approach to Power Control in Cellular CDMA

In this paper, we present the power control problem in CDMA wireless data networks in the analytical setting of non-cooperative game theory. User satisfaction is represented as a net utility function, which is the difference of a strictly concave function, based on signal to interference ratio, and a cost term on user’s power. A detailed analysis for the existence and uniqueness of Nash equilibrium for the above non-cooperative game is presented. Next, a decentralized power control algorithm is developed which converges to the Nash Equilibrium, as demonstrated by both analytical and simulation methods. The framework is then extended to the multi-cell case, making user utilities depend on base-station assignment as well as powers. We propose a generalized algorithm that can handle base station assignment and hand-off, as well as power control, and study by extensive simulations its performance in a dynamic environment.