Priority-Based Device Discovery in Public Safety D2D Networks with Full Duplexing

Device-to-device (D2D) services are gaining popularity in public safety (PS) applications. The existing half-duplex (HD) D2D discovery has the constraint that the devices sending beacon cannot be discovered at the same time, resulting in large time delays. To counter this problem, in-band full duplex (IB-FD) communications can be used to discover the user quickly by enabling simultaneous transmission and reception during same time-frequency block. In this paper, we exploit the benefits of IB-FD system where PS users are given priority in resource allocation. Moreover, to efficiently utilize the spectrum, we propose a time-efficient device discovery resource allocation (TE-DDRA) scheme where a user can switch the transmission mode from HD to IB-FD when the demand exceeds the available resources in HD mode. The simulation results prove that in comparison with random mode, the PS priority mode saves around \(37\%\) discovery time.