A Game Theoretic Solution for Exploiting Multiuser Diversity in Cooperative Slotted Aloha

In multiuser systems, multiuser diversity gains can be achieved by assigning channels to users with higher channel quality. To avoid the extensive information exchange required for centralized approaches, we propose a distributed fair pricing strategy for a slotted ALOHA system in which users act selfishly to improve their own utilities. Based on a game theoretic framework, we show that multiuser diversity gains can be achieved by appropriately designing the Nash equilibrium thresholds for the selfish users, such as to preserve the throughput and revenue achieved in the centralized schemes. The network enforces fairness among different users by employing a pricing policy that favors equal access probabilities. Our simulation results show significant multiuser diversity gains achieved in terms of energy consumption and/or spectral efficiency.