Delay minimization by exploring full-duplex capacity and relay-based cooperative scheduling in WLANs

The research breakthrough on the hardware implementation of wireless fullduplex transmission has attracted significant interests on building full-duplex wireless networks in recent years. However, due to the asymmetry of real traffic flows, it is challenging to improve the network performance by effectively utilizing the full-duplex capacity. In this paper, we investigate the transmission delay minimization problem of full-duplex WLANs under ad-hoc mode. We first derive a lower bound of the total transmission delay and then propose a relay-based cooperative schedule scheme named CR-Mechanism, via exploiting eligible full-duplex communication opportunities. Our theoretical analysis shows that it achieves such lower bound with a polynomial-time complexity. Furthermore, the closed-form expressions of the expectation of total delay, time saving and transmission cost of CR-Mechanism are also derived. The extensive experimental results confirm that CR-Mechanism is an optimal scheduling algorithm with better performance than conventional mechanisms under different traffic models.