Distributed Access in Full-duplex Directional Multi-Packet Reception Wireless Networks

This paper investigates novel techniques for enabling efficient and scalable access in future 6G wireless networks, specifically focusing on grant-free access methods. Motivated by multi-packet reception (MPR) techniques such as those already utilized in 5G networks employing Zadoff-Chu sequences, we study the performance of MPR systems jointly with directional and in-band full-duplex (IBFDX) communications at the physical layer. The directional approach facilitates more efficient frequency spatial reuse, while IBFDX enables transmitters to simultaneously transmit and receive over the same spectrum, thus enhancing spectral efficiency. To organize the grant-free distributed access, we propose a two-stage reservation-based MAC protocol tailored to the considered scenario. By employing simulation and model-based evaluations, we demonstrate the scalability and efficiency gains of the proposed PHY/MAC cross-layer scheme in a mobile network. The simulation results underscore the critical importance of the proposed model in optimizing the network throughput. By bridging advancements in PHY and MAC layers and leveraging innovative techniques such as MPR, directional communications, and in-band full duplex, our study contributes to the foundational development of more scalable and efficient access methods for upcoming 6G networks.