Cooperative D2D discovery approach for public safety based on spreading technique

摘要

In world news, natural disasters are frequently cited. Their devastating consequences make of them a crucial study subject to decrease their impact. Scientific researchers take advantage of 3GPP and D2D communication to help to save lives. D2D technology can be an alternative communication in a natural disaster situation with a total or partial absence of network infrastructure. Victims must be able to transmit SOS messages using their devices even in presence of other victims transmission or other systems communication to guarantee their detection. In this paper, we propose to consider that a receiver probes all physical resource blocs in a given spectrum band based LTE networks in order to be able to detect victims. Spreading technique is used when an SOS is transmitted and correlation is analysed in the receiver side in order to decide whether a victim is using a Resource Bloc to ask for help or not. We propose, as well, to multiply the number of receivers in different locations. This will let us to exploit the users diversity in order to enhance the detection accuracy based on hard information combining. Hence, receivers will cooperate to derive a reliable decision about an SOS transmission. Their hard decisions will be gathered by a fusion center and combined based on OR, AND, Majority and Two Witnesses Rules. Finally, simulations were carried out to prove the effectiveness of our proposed scheme based on the analysis of the detection, mis-detection and false alarm probabilities.