Transmission Probability Control Game for Coexisting Random ALOHA Wireless Networks in Unlicensed Bands

In this paper, we consider N ad hoc networks, with nodes randomly and uniformly distributed, coexisting and sharing an unlicensed band. The objective of this paper is the optimization of the transmission probabilities in these networks to maximize the throughput in each network. Throughput in each system is limited by the self interference (the interference inflicted by a network on its own nodes) as well as the interference from the other networks. We consider the coexisting wireless networks being independent and random. Each network uses a random access method with its own transmission attempt probability. We show that the throughput in each network depends on the choice of transmission probabilities of all networks. We use the game theory approach to solve the transmission probability control problem. Simulation result indicate that at the Nash equilibrium a closely optimal solution can be obtained. We also consider the fairness and show that the transmission chances of systems are fairly equalized at the NE solutin. This contrasts with the centralized solution in which there is high discrepancy among the transmission probabilities.