5G NR (5G New Radio) is a wireless network standard for the next (i.e., fifth) generation of mobile networks. 3GPP (Third Generation Partnership Project) is expecting to complete the NR specification in two phases. Phase I will be completed in June 2018 (3GPP Release 14) and Phase II in December 2019 (3GPP Release 15) [3GPP-1].
NR aims to provide a single technical framework addressing a broad range of use cases, requirements and deployment models, including [3GPP-1]:
NR aims to meet the 5G requirements outlined by ITU-R (International Telecommunication Union Radiocommunication Sector) for IMT-2020 (International Mobile Telecommunication system) in the IMT-2020 recommendation document (see reference [ITU-R-1]). 3GPP will submit NR as a candidate technology to the IMT-2020 process. Initial submission is expected to happen by June 2019, and a detailed specification will be submitted by October 2020. The IMT-2020 capabilities include [ITU-R-1]:
NR will be using both more traditional cellular access bands below 6 GHz and large amounts of spectrum available above 6 GHz [NOK-1]. In fact, NR should be able to use any spectrum band ranging at least up to 100 GHz that may be made available for wireless communications [3GPP-1]. NR will be using [QC-1]:
The frequency bands between 3 GHz and 30 GHz are known as centimeter wave (cmWave) bands, whereas bands between 30 GHz and 300 GHz are known as millimeter wave (mmWave) bands. At mmWave frequencies, the radio propagation and Radio Frequency (RF) engineering is different from the traditional sub-6 GHz cellular access bands. For example, diffraction (short radio waves are affected more by obstacles than long radio waves [LR-1]), foliage (radio signal running into leaves on a tree), and structure penetration losses (penetration loss of radio waves for example through walls of a building tends to increase with frequency [ITU-R-2]) are higher at mmWave frequencies [NOK-1]. However, mmWave frequencies are still similar to sub-6 GHz frequencies when it comes to reflections and path loss exponents. mmWave’s reach and ability to support mobility can be extended from Line-of-Sight (LOS) to Non-Line-of-Sight (NLOS) scenarios with beamforming and beamtracking by leveraging reflected and scattered radio waves [AT-1, INF-1]. Telecom vendors have demonstrated very high data rates using mmWave spectrum (e.g., 15 Gbps at 73 GHz with 2 GHz bandwidth [NOK-1]).
NR is still work-in-progress since its standardization is currently ongoing in 3GPP. However, it is possible to extract various likely NR features for example from the latest 3GPP documents, and vendor and operator white papers and press releases. These include:
Finally, even though they were the focus of this blog post, 5G is much more than a NR-based new radio access network and additional spectrum. There are plenty of developments also in the transport network and core network that deserve to be discussed in future blog posts, including for example network slicing, programmable network, service chaining (a.k.a., Service Function Chaining; SFC), Software-Defined Networking (SDN), Network Functions Virtualization (NFV), Next Generation Core (NGC), Cloud-RAN, virtual cells, xhaul, Core Network as-a-Service (CNaaS), RAN as-a-Service (RANaaS), end-to-end management and orchestration, Mobile Edge Computing (MEC), and the use of Machine Learning (ML) and Artificial Intelligence (AI). In addition to NR, many of these technologies will be needed to make 5G a platform that is capable of providing extreme bandwidth, extremely low latency, extreme reliability, extreme coverage, extreme flexibility, and security to cater for the needs of a broad range of use cases.
[3GPP-1] 3GPP TR 38.912 V1.0.0 (2017-03), 3rd Generation Partnership Project; Technical Specification Group Radio Access Network; Study on New Radio (NR) Access Technology (Release 14), http://www.3gpp.org/ftp//Specs/archive/38_series/38.912/38912-100.zip
[3GPP-2] Tentative 3GPP timeline for 5G, http://www.3gpp.org/news-events/3gpp-news/1674-timeline_5g
[3GPP-3] 3GPP TR 22.886 V15.1.0 (2017-03), Technical Report, 3rd Generation Partnership Project; Technical Specification Group Services and System Aspects; Study on enhancement of 3GPP Support for 5G V2X Services (Release 15), https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=3108
[AT-1] Millimeter-wave 5G modem coming mid-2018 with 5Gbps peak download, https://arstechnica.com/business/2016/10/qualcomm-5g-x50-modem-millimetre-wave-5g-modem/
[ERIC-1] Ericsson White paper, 5G Radio Access, https://www.ericsson.com/res/docs/whitepapers/wp-5g.pdf
[HW-1] 5G: A Technology Vision, http://www.huawei.com/5gwhitepaper/
[INF-1] Introduction to Millimeter Wave Wireless Communications, http://www.informit.com/articles/article.aspx?p=2249780
[ITU-R-1] Recommendation ITU-R M.2083-0 (09/2015), IMT Vision – Framework and overall objectives of the future development of IMT for 2020 and beyond, https://www.itu.int/dms_pubrec/itu-r/rec/m/R-REC-M.2083-0-201509-I!!PDF-E.pdf
[ITU-R-2] Recommendation ITU-R P.2040-1 (07/2015), Effects of building materials and structures on radiowave propagation above about 100 MHz, https://www.itu.int/dms_pubrec/itu-r/rec/p/R-REC-P.2040-1-201507-I!!PDF-E.pdf
[LR-1] Vodafone CTO 'Worried' About 5G mmWave Hype, http://www.lightreading.com/mobile/spectrum/vodafone-cto-worried-about-5g-mmwave-hype/d/d-id/730679
[NGMN] NGMN 5G White Paper, https://www.ngmn.org/uploads/media/NGMN_5G_White_Paper_V1_0.pdf
[NOK-1] 5G Radio Access System Design Aspects, http://resources.alcatel-lucent.com/asset/200009
[QC-1] Making 5G NR A Reality, https://www.qualcomm.com/documents/making-5g-nr-reality
NR aims to provide a single technical framework addressing a broad range of use cases, requirements and deployment models, including [3GPP-1]:
- enhanced Mobile BroadBand (eMBB) – MBB is the use case for which the previous generations of mobile networks have primarily been optimized
- Massive Machine Type Communications (M-MTC), which is also known as Massive Internet of Things (M-IoT)
- Ultra-Reliable and Low-Latency Communications (URLLC), which is also referred to as Critical MTC (C-MTC) or Critical IoT (C-IoT)
NR Capabilities
NR aims to meet the 5G requirements outlined by ITU-R (International Telecommunication Union Radiocommunication Sector) for IMT-2020 (International Mobile Telecommunication system) in the IMT-2020 recommendation document (see reference [ITU-R-1]). 3GPP will submit NR as a candidate technology to the IMT-2020 process. Initial submission is expected to happen by June 2019, and a detailed specification will be submitted by October 2020. The IMT-2020 capabilities include [ITU-R-1]:
- Peak data rate of 20 Gbit/s per user or device. This is the maximum achievable data rate under ideal conditions. For IMT-Advanced (i.e., LTE), the peak data rate is 1 Gbit/s.
- User experienced data rate of 100 Mbit/s in wide-area coverage cases (e.g., urban and sub-urban areas). This is the data rate that is available ubiquitously across the coverage area to a user or device. In hotspot areas (e.g., indoors), the user experienced data rate is expected to be 1 Gbit/s. For IMT-Advanced, the user experienced data rate is 10 Mbit/s.
- Latency of 1ms. This is the contribution of the radio network to the end-to-end latency (i.e., the over-the-air latency). For IMT-Advanced, the latency is 10ms.
- Mobility for up to 500 km/h (e.g., when the user is on a high-speed train). This is the maximum speed at which a defined QoS and seamless transfer between radio nodes can be achieved. For IMT-Advanced, the maximum speed is 350 km/h
- Connection density of one million devices per square kilometer. For IMT-Advanced, the figure is 100,000 per km^2
- Network energy efficiency of 100 times higher than for IMT-Advanced
- Spectrum efficiency that is three times higher than for IMT-Advanced
- Area traffic capacity of 10 Mbit/s/m^2. This is the traffic throughput served per geographic area. This represents a 100x improvement over IMT-Advanced
- Spectrum and bandwidth flexibility, such as the ability to operate at different frequency ranges, including higher frequency (e.g., millimeter wave) and wider channel bandwidths than today
- Reliability, that is, the capability to provide a given service with very high availability
- Resilience, which refers to the ability of the network to continue operating for instance after natural disturbances
- Security and privacy, including encryption and integrity protection of user data and signaling, end user privacy (e.g., preventing unauthorized user tracking), and protection of network against hacking, fraud, Denial of Service (DoS), man-in-the-middle attacks, etc.
- Long operational lifetime, which is important for IoT devices that require a very long battery life (e.g., more than 10 years)
- Massive densification of small cells – due to constraints on spectrum efficiency (Shannon’s law) and use of higher frequency spectrum, cell densification is needed for 5G to be able to deliver the required data rate and capacity improvements [NGMN]
- Additional spectrum (see below)
- Increased spectral efficiency, for which a key technology will be massive MIMO (Multiple Input Multiple Output)
Spectrum
NR will be using both more traditional cellular access bands below 6 GHz and large amounts of spectrum available above 6 GHz [NOK-1]. In fact, NR should be able to use any spectrum band ranging at least up to 100 GHz that may be made available for wireless communications [3GPP-1]. NR will be using [QC-1]:
- Low bands below 1 GHz to achieve longer range for example for mobile broadband and massive IoT. The could include for example 600 MHz, 700 MHz, and 850/900 MHz
- Mid bands from 1 GHz to 6 GHz to provide wider bandwidth for example for eMBB and critical IoT. Examples include 3.4 - 3.8 GHz, which includes also the CBRS (Citizens Broadband Radio Service) bands, 3.8 - 4.2 GHz, and 4.4 – 4.9 GHz.
- High bands above 24 GHz, which will be helpful for reaching extreme bandwidths. Examples include 24.25 – 27.5 GHz, 27.5 – 29.5 GHz, 37-40 GHz, and 64 – 71 GHz.
The frequency bands between 3 GHz and 30 GHz are known as centimeter wave (cmWave) bands, whereas bands between 30 GHz and 300 GHz are known as millimeter wave (mmWave) bands. At mmWave frequencies, the radio propagation and Radio Frequency (RF) engineering is different from the traditional sub-6 GHz cellular access bands. For example, diffraction (short radio waves are affected more by obstacles than long radio waves [LR-1]), foliage (radio signal running into leaves on a tree), and structure penetration losses (penetration loss of radio waves for example through walls of a building tends to increase with frequency [ITU-R-2]) are higher at mmWave frequencies [NOK-1]. However, mmWave frequencies are still similar to sub-6 GHz frequencies when it comes to reflections and path loss exponents. mmWave’s reach and ability to support mobility can be extended from Line-of-Sight (LOS) to Non-Line-of-Sight (NLOS) scenarios with beamforming and beamtracking by leveraging reflected and scattered radio waves [AT-1, INF-1]. Telecom vendors have demonstrated very high data rates using mmWave spectrum (e.g., 15 Gbps at 73 GHz with 2 GHz bandwidth [NOK-1]).
Likely NR Features
NR is still work-in-progress since its standardization is currently ongoing in 3GPP. However, it is possible to extract various likely NR features for example from the latest 3GPP documents, and vendor and operator white papers and press releases. These include:
- Access/backhaul integration [ERIC-1]
- Carrier Aggregation (CA) evolution [QC-1]
- Direct Device-to-Device (D2D) communication [ERIC-1]
- Flexible duplex (FDD (Frequency Division Duplexing) and TDD (Time Division Duplexing)) [ERIC-1] / dynamic uplink/downlink (UL/DL) switching [QC-1]
- Multi-antenna transmission [ERIC-1], which could include Massive MIMO (Multiple Input Multiple Output) [QC-1], FD-MIMO (Full-Dimension MIMO; 3D beamforming) [QC-1], Multi-User MIMO (MU-MIMO), hybrid beamforming, distributed MIMO, adaptive beamforming and beamtracking
- Multi-Connectivity (including NR, LTE, Wi-Fi) [QC-1]
- Narrowband 5G (NB-5G), supporting e.g., RSMA (Resource Spread Multiple Access) and multi-hop mesh [QC-1]
- NR-based MulteFire [QC-1]
- NR-based Licensed Assisted Access (LAA) [QC-1]
- NR-based tiered sharing of spectrum utilizing CBRS (Citizens Broadband Radio Service) and LSA (Licensed Shared Access) [QC-1]
- OFDM (Orthogonal Frequency Division Multiplexing) based waveform (also LTE uses OFDM) [3GPP-1]
- Scalable numerology with scaling of subcarrier spacing [QC-1]
- Scalable Transmission Time Interval (TTI) [QC-1]
- Self-backhauling [HW-1]
- Self-contained integrated subframe design [QC-1]
- Ultra-lean design [ERIC-1]
- User/control separation [ERIC-1]
- V2X (Vehicle-to-Everything) [QC-1, 3GPP-3]
5G beyond NR
Finally, even though they were the focus of this blog post, 5G is much more than a NR-based new radio access network and additional spectrum. There are plenty of developments also in the transport network and core network that deserve to be discussed in future blog posts, including for example network slicing, programmable network, service chaining (a.k.a., Service Function Chaining; SFC), Software-Defined Networking (SDN), Network Functions Virtualization (NFV), Next Generation Core (NGC), Cloud-RAN, virtual cells, xhaul, Core Network as-a-Service (CNaaS), RAN as-a-Service (RANaaS), end-to-end management and orchestration, Mobile Edge Computing (MEC), and the use of Machine Learning (ML) and Artificial Intelligence (AI). In addition to NR, many of these technologies will be needed to make 5G a platform that is capable of providing extreme bandwidth, extremely low latency, extreme reliability, extreme coverage, extreme flexibility, and security to cater for the needs of a broad range of use cases.
References
[3GPP-1] 3GPP TR 38.912 V1.0.0 (2017-03), 3rd Generation Partnership Project; Technical Specification Group Radio Access Network; Study on New Radio (NR) Access Technology (Release 14), http://www.3gpp.org/ftp//Specs/archive/38_series/38.912/38912-100.zip
[3GPP-2] Tentative 3GPP timeline for 5G, http://www.3gpp.org/news-events/3gpp-news/1674-timeline_5g
[3GPP-3] 3GPP TR 22.886 V15.1.0 (2017-03), Technical Report, 3rd Generation Partnership Project; Technical Specification Group Services and System Aspects; Study on enhancement of 3GPP Support for 5G V2X Services (Release 15), https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=3108
[AT-1] Millimeter-wave 5G modem coming mid-2018 with 5Gbps peak download, https://arstechnica.com/business/2016/10/qualcomm-5g-x50-modem-millimetre-wave-5g-modem/
[ERIC-1] Ericsson White paper, 5G Radio Access, https://www.ericsson.com/res/docs/whitepapers/wp-5g.pdf
[HW-1] 5G: A Technology Vision, http://www.huawei.com/5gwhitepaper/
[INF-1] Introduction to Millimeter Wave Wireless Communications, http://www.informit.com/articles/article.aspx?p=2249780
[ITU-R-1] Recommendation ITU-R M.2083-0 (09/2015), IMT Vision – Framework and overall objectives of the future development of IMT for 2020 and beyond, https://www.itu.int/dms_pubrec/itu-r/rec/m/R-REC-M.2083-0-201509-I!!PDF-E.pdf
[ITU-R-2] Recommendation ITU-R P.2040-1 (07/2015), Effects of building materials and structures on radiowave propagation above about 100 MHz, https://www.itu.int/dms_pubrec/itu-r/rec/p/R-REC-P.2040-1-201507-I!!PDF-E.pdf
[LR-1] Vodafone CTO 'Worried' About 5G mmWave Hype, http://www.lightreading.com/mobile/spectrum/vodafone-cto-worried-about-5g-mmwave-hype/d/d-id/730679
[NGMN] NGMN 5G White Paper, https://www.ngmn.org/uploads/media/NGMN_5G_White_Paper_V1_0.pdf
[NOK-1] 5G Radio Access System Design Aspects, http://resources.alcatel-lucent.com/asset/200009
[QC-1] Making 5G NR A Reality, https://www.qualcomm.com/documents/making-5g-nr-reality
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