On D2D communications for public safety applications

Providing seamless wireless coverage is essential for maintaining reliable communications in cellular networks. However, in extraordinary circumstances such as catastrophes, cellular infrastructure could be severely damaged; therefore, coverage is lost. For this reason, device-to-device (D2D) communication emerged as a promising technology to maintain wireless connectivity especially for search and rescue missions. This paper presents a review on recent advances in D2D communications regarding public safety applications such as search and rescue missions, coverage extension, and road safety. In search and rescue missions, discovery of devices in impacted areas can be achieved by other devices that have access to the cellular network. Moreover, the close proximity among mobile devices enables high data rate provisioning thus allowing rescue teams to send real-time high quality video and image reports to control centers. Cellular coverage can also be extended using relays such as drones that could play a significant role in coverage extension in extraordinary conditions. Furthermore, the safety of roads can be highly improved with vehicle-type communications, whereby information among vehicles are exchanged to avoid collisions.