Emergency Route Selection for D2D Cellular Communications During an Urban Terrorist Attack

Device-to-Device (D2D) communications is a technology that allows mobile users to relay information to each other, without access to the cellular network. In this paper, we consider how to dynamically select multi-hop routes for D2D communications in spectrum co-existence with a fully loaded cellular network. The modelling scenario is that of a real urban environment, when the cellular network is congested during an unexpected event, such as a terrorist attack. We use D2D to relay data across the urban terrain, in the presence of conventional cellular (CC) communications. We consider different wireless routing algorithms, namely: shortest-path-routing (SPR), interference-aware-routing (IAR), and broadcast-routing (BR). In general, there is a fundamental trade-off between D2D and CC outage performances, due to their mutual interference relationship. For different CC outage constraints and D2D end-to-end distances, the paper recommends different D2D routing strategies. The paper also considers the effects of varying user density and urban building material properties on overall D2D relaying feasibility. Over a distance of a kilometre, it was found that the success probability of D2D communications can reach 91% for a moderate participating user density (400 per square km) and a low wall penetration loss (<10dB).Comment: IEEE International Conference on Communications (ICC

Optimizing Device-to-Device Communications in Cellular Networks

In this report, we consider how to dynamically select transmission bands and multi-hop routes for device-to-device (D2D) communications in co-existence with a cellular network overlay. Firstly, we consider different wireless routing algorithms, i.e. broadcasting-routing (BR) method, and shortest-path-routing (SPR) method. The results show that depending on the co-existence cellular users' outage constraint, different routing strategies have different merits. BR is acceptable at the low D2D user density but is terrible at high density. We also consider the channel band performance (Uplink band and Downlink band). The results show that the multi-hop D2D can achieve a low outage probability using the uplink band (approximately 5%), and D2D in the downlink band performs a little poorly (approximately 12%) outage with SPR