Toward 5G Emerging Technologies: Selected Papers from IEEE PIMRC 2014

Abstract

Preface The fifth generation of wireless access technology (5G) is facing a daunting task of meeting constant demands for higher data rates and system capacity, as well as wide range of applications and users’ quality of experience (QoE) requirements. Although not standardized yet, 5G technology is expected to offer significantly higher throughput than long-term evolution (LTE), have a latency in the low milliseconds and be able to accommodate and support the anticipated explosion in the Internet of Things (IoT) devices. New device types (e.g. probes, meters, sensors, actuators) will significantly contribute to traffic increase and new market sectors will bring new priorities (e.g. critical infrastructures). Tentative timeline for 5G standardization is around 2018–2019 (i.e. release 14 or 15 of the 3GPP standards) with anticipated roll-outs in 2020 time frame. Use of millimeter wave (mmWave) technology is expected to be a significant part of the 5G innovations; and according to its advocates, the spectrum has the potential to initiate new businesses and use cases once appropriate regulatory agencies makes it available. Massive multiple-input multiple output (MIMO), Software Defined/Cognitive Radios, Cloud-based Networks, Self-Organized Cells, Device to Device Communications are among other technologies that could potentially be used in 5G systems. Breakthrough energy-efficient hardware and software will most likely be employed to make 5G systems ‘‘green’’. Wireless technology has enormous potential to change the way we live, work, and behave. 5G is envisioned to extend traditional services from enhanced mobile broadband to vertical markets such as connected cars, industry automation, smart metering and health care. However, there are still many technical challenges that must be overcome in order to make this vision a reality. Although the exact pathways to 5G systems, devices, and architectures is still under development, massive growth in applications and data consumption by mobile consumers will be a strong driver to push the industry toward that technology. The papers which appear in this special issue have been carefully selected from the best IEEE PIMRC 2014 conference papers addressing some of the challenging issues related to the emerging 5G technologies. The invited authors have been asked to provide a significantly extended version of their respective conference papers, which have subsequently undergone a rigorous review process according to the IJWIN publication standards prior to acceptance. The final set of papers address various challenging issues such as user cooperation in 5G radio access networks, cost effective deployment addressing on-demand capacity, beamforming in mmWave MIMO transceivers, coexistence and efficient multi-carrier resource allocation. Our objective is to give the reader a perspective on current technical achievements and also future challenges and possible development in this exciting area. We sincerely hope that you enjoy reading the interesting and highquality research works presented here. The authors of the first paper ‘‘User Cooperation for 5G Wireless Access Networks’’ address device-to-device (D2D) connectivity as one of the main enablers of future 5G radio access networks. Specifically, they introduce a & Kamran Sayrafian ksayrafian@nist.gov