Energy-efficient joint BS-RS sleep scheduling based on cellular automata in relay-aided cellular networks

In this paper, a joint Base Station (BS) and Relay Station (RS) sleep scheduling algorithm is proposed for relay-aided cellular networks based on Cellular Automata (CA). By applying the self-organizing character of CA, the number of active BSs and RSs converges to a stable state to save energy. A suboptimal value of energy efficiency of the relay-aided cellular network is obtained via a CA algorithm. Furthermore, a branch and bound algorithm based on the denominator interval values of the objective function is developed to maximize energy efficiency under the spectral efficiency constraint. Convergence of the number of active BSs and RSs is demonstrated by numerical simulations, which shows effectiveness of the proposed branch and bound algorithm is superior to the random sleep scheme and the scheme without sleep scheduling.