Transmit-time allocation in wireless sensor relay transmission with energy fairness

Cooperative transmission is an efficient method for wireless sensor networks (WSN) to decrease the power consumption of sensor transmitter and counter the detrimental effect of signal fading inherent to wireless channels. During the course, a key issue is how the sensor relay should handle the balance of assisting other node´s communications and accomplishing its own tasks and what kind of situation the sensor transmitter needs to ask for the cooperation rather than direct communication. In this paper, we investigate the potential bargaining for resource allocation in WSN over Rayleigh fading environments to address the problems by considering the energy fairness for both the participants of the cooperative transmission. Based on Rayleigh fading channels´ characteristics, a relevant system model is first built. Then, after analyzing the system capacity in given outage probability over the fading channels, a system utility function with regard to the transmit-time allocation addressing both participants´ energy concern is proposed. An iterative algorithm is subsequently achieved by solving the Nash equilibrium. Furthermore, essential analyses and discussions on the equilibrium existence and convergence conditions of the iterative algorithm are provided.