A full-duplex MAC technique to improve spectrum-efficiency on 5G mobile wireless networks

Abstract

Full-duplex (FD) communications shall play an important role on the next generation (5G) mobile wireless networks as they are expected to enhance spectrum usage and throughput. Unleashing the benefits of FD communications, however, requires a fitted design of medium access control (MAC) schemes. In spite of that, existing full-duplex MAC schemes are build upon the IEEE 802.11 which is designed to operate on half-duplex radios. The main contribution of this work is to propose a full-duplex communication mechanism devised to improve spectrum usage and throughput in the context of FD communications. The proposed scheme, named Full-Duplex Dynamic Scheduling MAC (FDDS-MAC), uses a novel strategy to select a communicating pair that maximizes the probability of establishing a full-duplex communication between sending and receiving nodes. A mathematical analysis of the proposed strategy is presented to show the potential improvement that can be achieved using FDDS-MAC. Moreover, in order to compare FDDS-MAC throughput with state-of-art full-duplex communications mechanisms, an analytical model addressing the details of a FD communication is proposed. Analytical evaluation shows that the proposed scheme provides throughput gain up to 50% as compared to the state-of-art full-duplex communications mechanisms. Furthermore, an enhanced version of FDDS-MAC (termed FDDS-MAC*) is proposed to further reduce the time spent selecting the receiver node that maximizes the probability of establishing a full-duplex communication. Numerical results reveals that FDDS-MAC* achieved an improvement over existing full-duplex MAC schemes up to 59% in terms of throughput, thus showing the positive impact of FDDS-MAC* deployment.