The authors present the five technologies for 5G that could lead to both architectural and component disruptions: (1) device-centric architectures, (2) millimeter wave; (3) massive MIMO; (4) smarter devices; and (5) native support for machine-to-machine communications. The key ideas for each technology are described, along with their potential impact on 5G and the research challenges that remain.
1) Device-centric architectures: The base-station-centric architecture of cellular systems may change in 5G. It may be time to reconsider such concepts as uplink and downlink, as well as control and data channels. 5G systems will use nodes on an ad hoc basis.
2) Millimeter wave (mmWave): While spectrum has become scarce at microwave frequencies, it is plentiful in the mmWave realm. Such a spectrum “el Dorado” has led to an mmWave “gold rush”. Although far from being fully understood, mmWave technologies have already been standardized for short-range services (IEEE 802.11ad) and deployed for niche applications such as small-cell backhaul.
3) Massive MIMO: Massive multiple-input multiple-output (MIMO) proposes using a very large number of antennas to spatially multiplex data. Massive MIMO may require major architectural changes, particularly in the design of macro base stations, and it may also lead to new types of deployments.
4) Smarter devices: 2G-3G-4G cellular networks were built under the design premise of having complete control at the infrastructure side. The proposal is for 5G systems to drop this design assumption and exploit intelligence at the device side within different layers of the software protocol stack. For example, one could allow device-to-device (D2D) connectivity or exploit smart caching at the mobile smartphone side. While this design philosophy mainly requires a change at the node level (component change), it also has implications at the architectural level.
5) Native support for machine-to-machine (M2M) communication: A native inclusion of M2M communication in 5G has three main requirements: support of a massive number of low-data-rate devices, sustaining a minimal data rate in virtually all circumstances, and very-low-latency data transfer. Addressing these requirements in 5G requires new methods and ideas at both the component and architectural levels.
Title and author(s) of the original paper in IEEE Xplore: