Spectrum sharing in secondary networks: A bargain theoretic approach

In this paper, we address the problem of dynamic channel access by a set of cognitive radio enabled nodes (e.g., broadcast access points), where each node acting in a selfish manner tries to access and use as many channels as possible, subject to the interference constraints. We model the dynamic channel access problem as a modified Rubinstein-Ståhl bargaining game. In our model, each node (player) negotiates with the other nodes to obtain an agreeable sharing rule of the available channels, such that, no two interfering nodes use the same channel. We solve the bargaining game by finding Subgame Perfect Nash Equilibrium (SPNE) strategies of the game. First, we consider finite horizon version of the bargaining game and investigate its SPNE strategies. We then extend these results to the infinite horizon bargaining game. Furthermore, we identify Pareto optimal equilibria of the game for improving spectrum utilization. The bargaining solution ensures that no node is starved of channels. We also conduct extensive simulations to study how the “self-gain” maximizing strategy of the players impact system wide performance.