A Game Theoretic Framework for Call Admission Control in CDMA Mobile Multimedia Systems with Traffic Asymmetry between Uplink and Downlink

In code-division multiple-access (CDMA) mobile multimedia systems, call admission control (CAC) is essential to prevent overloading and ensure quality of service (QoS) requirement for each traffic class. While efficiency is an important performance issue in the mobile networks with multimedia services, the concept of fairness among services should also be considered. Game theory can provide an appropriate framework for formulating such fair and efficient CAC problem. In this paper, a selection method for fair-efficient threshold parameters of the CAC scheme in CDMA mobile multimedia systems with traffic asymmetry based on the framework of game theory is proposed. The proposed scheme provides fairness and efficiency in terms of uplink and downlink signal-to-interference ratio (SIR) for the 2 classes of traffic, and also guarantees the priority of class 0 calls over class 1 calls. Class 0 calls and class 1 calls are viewed as two players of a game. For the cooperative game, the arbitration schemes for the interpersonal comparisons of utility and the bargaining problem are investigated. In the aspect of the social welfare (total utility), the numerical results indicate that the Nash solution of the bargaining problem outperforms the equilibrium point of the noncooperative game and the solution of the interpersonal comparisons of utility due to its much higher total utility.