Buffering Time for Wireless Full-Duplex Systems Under Random Arrival

Full-duplex wireless communication has the potential to double the capacity of wireless networks by reducing the duration ratio of band occupancy of transmissions. However, under practical non-fully buffered traffic, a full-duplex capability cannot always reduce the duration ratio of band occupancy, the time ratio at which one network occupies the radio channel. Buffering time while waiting for a packet to arrive at an opposite node is expected to reduce the duration ratio of band occupancy. In this paper, we provide the theoretical analysis of the duration ratio of band occupancy and the mean waiting time for full-duplex communication with and without buffering time under traffic that is not fully buffered based on the queueing theory as well as the closed-form results. We also present the results of simulations of the duration ratio of band occupancy and the mean waiting time. The basic analysis provided in this paper shows how the mean waiting time and the duration ratio of band occupancy are affected by the buffering time. Under practical unsaturated asymmetrical up and down traffic load, the results suggest that the buffering time should not be set at the node which has a higher traffic intensity compared with another node. In addition, when the buffering time is half the packet length, the duration ratio of band occupancy is reduced by approximately 15%.