The next generation of wireless communications must support a wide range of applications and services. Recent advances in wireless applications and services have shown a fast growth in mobile traffic with prospects to increase in coming years. So-called 5G applications, Internet of things (IoT), and machine-to-machine (M2M) applications require massive connectivity of users and/or autonomous devices to meet the demand of diverse services in terms of low cost, low latency, reliability, and throughput.
New technologies are being developed to respond to the traffic explosion. Currently, competing and complementary technologies like long-term evolution (LTE), IEEE 802.11 (WiFi), and IEEE 802.15 personal area networks (PANs) are developing standardized solutions. In particular, IEEE 802.15.8 is developing an international standard on device-to-device (D2D) communication networks that is infrastructure-less (devices do not need to access infrastructure for network synchronization, discovery, and communication), with distributed coordination and multicast/multigroup communications.
Peer-to peer communications or D2D is an active field of research and development as it has some interesting and important use cases. Indeed, in mission critical communications from public safety to highly reliable wireless systems in scenarios where access to infrastructure does not exist or was shut down due to natural disasters, D2D communications can offer real-time communication services infrastructure-less. On the other hand, D2D communications allow offloading traffic from LTE and WiFi networks for a group of neighboring users. This use case would be relevant in social networking, gaming, or emergency communications.
The current state of the art includes device-to-device communications for proximity services by LTE. WiFi Direct aims to replace the WiFi ad-hoc mode and proprietary systems such as FlashLinQ by Qualcomm. However, these systems still rely on infrastructure for (network) synchronization and/or discovery and management.
The IEEE 802.15.8 Peer-Aware-Communications (PAC) Task Group (TG8) aims to develop ad-hoc D2D communications, infrastructure-less, and with fully distributed coordination. This standard supports multicast sessions for group communications. Also, the proposed standard includes a in the recently released sub-GHz band, which allows the use of unmanned aerial vehicles (UAVs). Thus, PAC networks can combine aerial, terrestrial, and mobile D2D group communications.
The draft standard is currently under letter ballot, awaiting comments from the IEEE 802.15 and IEEE 802.19 Working Groups. The standard is expected to be published in the first quarter of 2017. The products envisioned in the standard range from gaming and social networks to emergency search and rescue operations. In the academy, the standard offers areas of research in distributed network synchronization, group communications, distributed MAC, etc.
Marco A. Hernandez
Marco A. Hernandez received a Ph.D. in electrical engineering from Delft University of Technology, The Netherlands. He was an International young graduate trainee with the European Space Research and Technology Center (ESTEC) in The Netherlands. He was a research assistant with the Faculty of Electrical Engineering, Delft University of Technology. He was an intern researcher in the Center for Communications and Signal Processing Research Laboratory (CCSPR) at New Jersey Institute of Technology, USA. He was a research assistant with the mobile communication group at Institute Eurecom in Sophia-Antipolis, France. He joined the Center of Excellence of the Graduate School of Electrical Engineering of Yokohama University, Japan. Currently, he is a senior researcher at the National Institute of Information and Communications Technology (NICT) in Yokosuka Research Park, Japan.