IEEE ComSoc opens the papers.
What the heck is 5G? Any big company will tell you 5G is whatever they happen to be planning. It's a meaningless marketing term. Another way to define 5G is "whatever advances are still to come." ComSoc has now pulled from behind the paywall four papers with expert opinion, all worth a read. Below are the abstracts and conclusions.
All agree that traffic will continue to grow and networks have to change to keep up. Massive MIMO and MU-MIMO, using many more than 8 antennas per cell site, will play a crucial role. Millimeter wave high frequencies have a role, at least in selected high density areas. Beyond that, opinions strongly differ, both in the papers and the overall discussion.
Must wireless networks be re-designed to store data and connect locally? Dan Warren, then the GSMA guru, believes the hoped for 1-millisecond latency in 5G networks was somewhere between impractical and impossible with today's network design.
Warren's comments at Light Reading's strong 5G Ecosystem event were among the last before he moved into a job at Capita, a big outsourcing company. Some telco suppliers suggest meeting the challenge by a major reorganization of the network, moving more intelligence to local nodes. It's not yet clear whether that would be worth the effort.
The Qualcomm team presents the advantages of Bottoms-up, WiFi First networks. My take is turning on the second SSID on home gateways is are the most cost and capacity efficient future. There's enormous incremental capacity available at virtually no cost.There's spare capacity at the gateway 95+% of the time. FON, the French and now the British and Germans have proven it works. Turning on this capacity is in the public interest; it's resisted by the phone companies because they charge for LTE but not WiFi. WiFi in fact is an existential threat to the current phone company business model.
NTT DOCOMO, under Seizo Onoe, is probably the most advanced planning the deployment of the new network. That makes their contribution particularly interesting although what's right for wireless only company DOCOMO is not right for many others.
5G by definition is the future of wireless, if we ever figure out just what 5G means.
Key points:
Bushan and Qualcomm team: Bottoms-up/WiFi First is a great, cheap way to add "5G" capacity.
Boccardi et. al.: Local connections and caching by smarter devices for speed and efficiency; High Frequency millimeter wave for capacity, MU-MIMO and M2M efficient low speed connections. They also point to the need for very high link reliability.
Wang et. al.: Cognitive radio will be ready, indoor and outdoor networks should be designed differently, energy efficiency will be crucial.
NTT DOCOMO team: "Networks must be able to support a target of 1 ms E2E latency with high reliability" but " 5G should be a network (RAN, core, backbone routers, and backhaul) that addresses all the new requirements at a cost that will make service provisioning sustainable. 5G should be a network (RAN, core, backbone routers, and backhaul) that addresses all the new requirements at a cost that will make service provisioning sustainable."
Five Disruptive Technology Directions for 5G
Federico Boccardi, Vodafone Robert W. Heath Jr., University of Texas at Austin Angel Lozano, Universitat Pompeu Fabra Thomas L. Marzetta, Bell Labs, Alcatel-Lucent Petar Popovski, Aalborg University
Key points: Local connections and caching by smarter devices for speed and efficiency; High Frequency millimeter wave for capacity, MU-MIMO and M2M efficient low speed connections. They also point to the need for very high link reliability.
ABSTRACT New research directions will lead to fundamental changes in the design of future fifth generation (5G) cellular networks. This article describes five technologies that could lead to both architectural and component disruptive design changes: device-centric architectures, millimeter wave, massive MIMO, smarter devices, and 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.
CONCLUSION This article has discussed five disruptive research directions that could lead to fundamental changes in the design of cellular networks. We have focused on technologies that could lead to both architectural and component design changes: device-centric architectures, mmWave, massive MIMO, smarter devices, and native support of M2M. It is likely that a suite of these solutions will form the basis of 5G.
Network Densification: The Dominant Theme for Wireless Evolution into 5G
Naga Bhushan, Junyi Li, Durga Malladi, Rob Gilmore, Dean Brenner, Aleksandar Damnjanovic, Ravi Teja Sukhavasi, Chirag Patel, and Stefan Geirhofer, Qualcomm Technologies, Incorporated
Key point: Bottoms-up/WiFi First is a great, cheap way to add "5G" capacity.
"An NSC network consists of small cells deployed (mostly by end users) in urban/suburban homes, small offices, and enterprises. NSC deployment involves no site acquisition and minimal RF planning, and uses existing broadband backhaul (digital subscriber line, DSL/cable) for core network connectivity. Plug-and-play user-driven NSC deployment with robust operation is achieved through self-organizing network (SON) techniques, as discussed below. These characteristics promote NSC network deployment with much-reduced cost compared to macro/pico deployment. A key functionality of an NSC network is “indoor-to-outdoor” coverage, that is, indoor small cells providing coverage to outdoor users Figure 2. Benefits of interference cancelation. Serving cell SNR (dB) -4 -2 0.5 0 Normalized throughput (b/s/Hz) 1 1.5 2 2.5 3 0 2 4 6 8 10 12 14 16 18 20 22 IC common signals (pilots, sync/broadcast) SLIC unicast and common signals SLIC unicast and common signals - blind detection BHUSHAN_LAYOUT_Layout 1/30/14 12:49 PM Page 84 (e.g., pedestrians, low-mobility vehicles) in the neighborhood. Thus, NSC constitutes a coverage layer that complements an existing macrocellular network. More significantly, by virtue of cell splitting, a dense NSC network can provide huge data capacity over macro-only deployment while maintaining seamless mobility across the entire (macro-NSC) network."
ABSTRACT This article explores network densification as the key mechanism for wireless evolution over the next decade. Network densification includes densification over space (e.g, dense deployment of small cells) and frequency (utilizing larger portions of radio spectrum in diverse bands). Large-scale cost-effective spatial densification is facilitated by self-organizing networks and intercell interference management. Full benefits of network densification can be realized only if it is complemented by backhaul densification, and advanced receivers capable of interference cancellation.
Conclusion: With reasonable projections on additional spectrum availability, expansion of small-cell deployments, and growth in backhaul infrastructure, we believe that the cellular communication industry is well positioned to meet the 1000x demand over the next decade. The path to 5G outlined in this article may seem like an enhancement and scaling of current 4G technologies with a few new components added in, but a combination of meaningful enhancements in key areas together with a few novel components can raise the overall user experience to a whole new level, inaugurating a brand new wireless universe that is truly worthy of the 5G designation. REFERENCES
Network Densification: The Dominant Theme for Wireless Evolution into 5G
ABSTRACT New research directions will lead to fundamental changes in the design of future fifth generation (5G) cellular networks. This article describes five technologies that could lead to both architectural and component disruptive design changes: device-centric architectures, millimeter wave, massive MIMO, smarter devices, and 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.
Cellular Architecture and Key Technologies for 5G Wireless Communication Networks
Cheng-Xiang Wang, Heriot-Watt University and University of Tabuk Fourat Haider, Heriot-Watt University Xiqi Gao and Xiao-Hu You, Southeast University Yang Yang, ShanghaiTech University Dongfeng Yuan, Shandong University Hadi M. Aggoune, University of Tabuk Harald Haas, University of Edinburgh Simon Fletcher, NEC Telecom MODUS Ltd. Erol Hepsaydir, Hutchison 3G UK
Key points: Cognitive radio will be ready, indoor and outdoor networks should be designed differently, energy efficiency will be crucial.
ABSTRACT The fourth generation wireless communication systems have been deployed or are soon to be deployed in many countries. However, with an explosion of wireless mobile devices and services, there are still some challenges that cannot be accommodated even by 4G, such as the spectrum crisis and high energy consumption. Wireless system designers have been facing the continuously increasing demand for high data rates and mobility required by new wireless applications and therefore have started research on fifth generation wireless systems that are expected to be deployed beyond 2020. In this article, we propose a potential cellular architecture that separates indoor and outdoor scenarios, and discuss various promising technologies for 5G wireless communication systems, such as massive MIMO, energy-efficient communications, cognitive radio networks, and visible light communications. Future challenges facing these potential technologies are also discussed.
CONCLUSIONS In this article, the performance requirements of 5G wireless communication systems have been defined in terms of capacity, spectral efficiency, energy efficiency, data rate, and cell average throughput. A new heterogeneous 5G cellular Figure 5. The ratio of ASE attained for the optical attocell network to ASE for the femtocell network against varying numbers of femtocells per floor. architecture has been proposed with separated indoor and outdoor applications using DAS and massive MIMO technology. Some short-range communication technologies, such as WiFi, femtocell, VLC, and mm-wave communication technologies, can be seen as promising candidates to provide high-quality and high-data-rate services to indoor users while at the same time reducing the pressure on outdoor BSs. We have also discussed some potential key technologies that can be deployed in 5G wireless systems to satisfy the expected performance requirements, such as CR networks, SM, MFemtocells, VLC, and green communications, along with some technical challenges.
Design Considerations for a 5G Network Architecture
Patrick Kwadwo Agyapong, Mikio Iwamura, Dirk Staehle, Wolfgang Kiess, and Anass Benjebbour
Key points: "Networks must be able to support a target of 1 ms E2E latency with high reliability" but " 5G should be a network (RAN, core, backbone routers, and backhaul) that addresses all the new requirements at a cost that will make service provisioning sustainable. 5G should be a network (RAN, core, backbone routers, and backhaul) that addresses all the new requirements at a cost that will make service provisioning sustainable."
ABSTRACT This article presents an architecture vision to address the challenges placed on 5G mobile networks. A two-layer architecture is proposed, consisting of a radio network and a network cloud, integrating various enablers such as small cells, massive MIMO, control/user plane split, NFV, and SDN. Three main concepts are integrated: ultra-dense small cell deployments on licensed and unlicensed spectrum, under control/user plane split architecture, to address capacity and data rate challenges; NFV and SDN to provide flexible network deployment and operation; and intelligent use of network data to facilitate optimal use of network resources for QoE provisioning and planning. An initial proof of concept evaluation is presented to demonstrate the potential of the proposal. Finally, other issues that must be addressed to realize a complete 5G architecture vision are discussed.
CONCLUSIONS The important challenges that must be addressed by 5G networks have been highlighted: higher capacity, higher data rate, lower E2E latency, massive device connectivity, reduced capital and operation cost, and consistent QoE provisioning. A 5G architecture vision to address some of those challenges is presented and a two-layer architecture proposed, consisting of a radio network and a network cloud. The proposed architecture integrates various enablers such as small cells, massive MIMO, C/U-plane split, NFV, and SDN. The main concepts can be summarized as follows: • Ultra-dense small cell deployments on licensed and unlicensed spectrum, under C/U-plane split architecture, to address capacity and data rate challenges • NFV and SDN to provide flexible network deployment and operation, with integrated AS and NAS features • Intelligent use of network data to facilitate optimal use of network resources for QoE provisioning and planning Initial proof of concept investigations suggest more than 1000 times throughput gains compared to a macro-only 3GPP Release 8 LTE deployment are achievable by a combination of dense deployment of small cells, using large bandwidths at higher frequency bands and employing massive MIMO techniques at small cells. Nevertheless, some of the components highlighted in the system concept have mutual conflicts when details are considered. Hence, how to balance the pros and cons of each aspect needs to be carefully studied. Further investigations are necessary, particularly in the following areas: suitable techniques for use in small cells in different frequency regimes; how to incorporate small cells with NFV and SDN in a costeffective manner; and intelligent algorithms that better utilize the available network resources to provide a consistent end-user QoE.
Cognitive radio will be ready, indoor and outdoor networks should be designed differently, energy efficiency will be crucial.
"Networks must be able to support a target of 1 ms E2E latency with high reliability" but " 5G should be a network (RAN, core, backbone routers, and backhaul) that addresses all the new requirements at a cost that will make service provisioning sustainable. 5G should be a network (RAN, core, backbone routers, and backhaul) that addresses all the new requirements at a cost that will make service provisioning sustainable."
the second SSID on home gateways.