Questions and answers about 5G (5G knowledge: 5GWorldPro.com)

Q: What is 5G

A: 5G is the 5th generation mobile network. It will take a much larger role than previous generations. 5G will elevate the mobile network to not only interconnect people, but also interconnect and control machines, objects, and devices. It will deliver new levels of performance and efficiency that will empower new user experiences and connect new industries. 5G will deliver multi-Gbps peak rates, ultra-low latency, massive capacity, and more uniform user experience.

Q: How fast is 5G? 

A: Per IMT-2020 requirements, 5G is expected to deliver peak data rates up to 20 Gbps. Till now Qualcomm Technologies’ first 5G NR modem, the Qualcomm® Snapdragon™ X50 5G modem, is designed to achieve up to 5 Gbps in downlink peak data rate. But 5G is more than about just how “fast” it is. In addition to higher peak data rates, 5G will provide much more network capacity by expanding into new spectrum, such as millimeter wave (mmWave). 5G will also deliver much lower latency for a quicker immediate response, and an overall more uniform user experience so that the data rates stay consistently high even when users are moving around. Moreover, the new 5G NR (New Radio) mobile network will be backed up by Gigabit LTE coverage foundation, which will provide ubiquitous Gigabit-class connectivity.

Q: When is 5G coming out? 

A: 5G should be available in 2019. 3GPP (3rd Generation Partnership Project, the standards body that is helping define 5G) made a decision to accelerate the initial phase of 5G NR (New Radio) – the new global 5G standard – to begin in 2019. It is important to note that initial 5G NR deployments will focus on enhanced mobile broadband (eMBB) use cases to boost capacity and provide an elevated mobile broadband experience (faster speeds, lower latencies, etc.). As with previous generations of mobile networks, it will take time to proliferate the new 5G network. 4G LTE will continue to grow and serve as the anchor of the 5G mobile experience (via multi-connectivity) for many years to come by providing Gigabit data rates outside 5G coverage areas.

Q: Is Massive MIMO mandatory for 5G deployment?

A: Massive MIMO is an essential technology for 5G deployments in mmWave bands where a large number of antennas is used to compensate for the propagation losses inherent to those high frequencies. However, in 5G deployments below 6GHz, Massive MIMO is optional and operators are still evaluating where and when to deploy these solutions effectively. The additional capacity usually comes at the expense of a significant additional CAPEX (and OPEX) investment compared to traditional radio+passive antenna solutions. Therefore, multiple operators are looking at xTxR radios + passive antennas are their de-facto 5G deployment option (from 600MHz to 4.5GHz bands), complemented with Massive MIMO where the business case makes sense.

Q. Is TDD preferred for 5G?

A: Most initial 5G deployments, both in sub 6GHz and mm Wave, will be based on TDD. The key advantages of TDD is that it allows dynamic sharing of Uplink and Downlink resources, thereby addressing the asymmetry in UL/DL traffic. TDD also provides increased efficiency for massive MIMO technology by exploiting channel reciprocity. TDD also allows un-utilized unpaired spectrum to be efficiently used, which otherwise would not have been possible if pairing was mandatory.

Q: What are the key differentiating 5G technologies? 

A: 5G is bringing a wide range of technology inventions in both the 5G NR (New Radio) air interface design as well as the 5G NextGen core network. The new 5G NR air interface introduces many foundational wireless inventions, and in our opinion, the top five are: 

Scalable OFDM numerology with 2n scaling of subcarrier spacing 

Flexible, dynamic, self-contained TDD subframe design 

Advanced, flexible LDPC channel coding 

Advanced massive MIMO antenna technologies 

Advanced spectrum sharing techniques

Q: How does 5G work? 

A: Like 4G LTE, 5G is also OFDM-based and will operate based on the same mobile networking principles. However, the new 5G NR (New Radio) air interface will further enhance OFDM to deliver a much higher degree of flexibility and scalability. 5G will not only deliver faster, better mobile broadband services compared to 4G LTE, but it will also expand into new service areas, such as mission-critical communications and connecting the massive IoT. This is enabled by many new 5G NR air interface design techniques, such as a new self-contained TDD subframe design

Q. How will 5G evolve in the complex spaces in high-traffic venues and in difficult-to-cover buildings and mega-structures?

A: Indoor venues will be a critical part of 5G. Industry analysts claim that 80 percent of all mobile traffic originates indoors, which will include 5G traffic. In addition, emerging 5G-dependent IoT applications such as smart retail and connected health are concentrated in commercial buildings. So, 5G will need to perform indoors as well as outdoors.  This will require specialized indoor solutions. 

Q: Will 5G RAN architecture allow open interfaces?

A: Traditionally RAN has been a closed architecture where the Base band and Radio are required to be from the same manufacturer, in order to be inter-operable. 5G RAN architecture has decomposed the RAN into three parts – Centralized Unit (CU), Distributed Unit (DU) and Radio Unit (RU) and 3GPP has specified the interface between DU and CU for multivendor scenarios (F1 interface). There is a massive interest in the industry to make the interfaces between these three functional units open. Notable being “ORAN Alliance” that has already specified an open fronthaul interface between the RU and the DU so that multivendor networks are enabled at all levels in the RAN. Open standardized interfaces will drive innovation in the industry and will allow multi-vendor implementations, enabling flexibility and programmability in Networks.

Q: What is role of NFV in 5G?

A: The basic idea behind NFV is to decouple software from hardware. With NFV, service providers can deploy various network functions, such as firewall or encryption, on virtual machines (VMs). Whenever a customer requests a new network function, service providers are able to spin up a VM for that function automatically. Leveraging this technology, network administrators do not need to invest in high-priced, proprietary hardware to set up a service chain of network-connected devices. And unlike proprietary hardware, these network functions can be installed in weeks instead of months. With respect to 5G, NFV will help virtualize multiple appliances in the network. Specifically, NFV will enable 5G network slicing, allowing various virtual networks to run on top of a single, physical infrastructure. Moreover, 5G NFV will allow a physical network to be divided into various virtual networks capable of supporting multiple radio access networks (RANs). NFV can also address barriers to 5G by optimizing resource provisioning of the virtual network functions (VNFs) for price and energy, scale VNFs and ensure VNFs consistently operate properly.

Q: What is role of SDN in 5G?

A: SDN is an intelligent, network architecture intended to minimize hardware constraints. The purpose of introducing SDN is to abstract lower level functions and move them to a normalized control plane, which manages network behavior through application program interfaces (APIs). From a software-based, centralized control plane, network administrators can provide services through the network despite the connected hardware components. With available spectrum, 5G is going to push the limits of what is achievable. This is where SDN fits into the 5G picture. SDN can be used to provide an overall framework to enable 5G to function across a control plane. It can provide better data flows as data moves across the 5G network. In addition, SDN architecture can minimize network bandwidth and boost latency. Finally, since SDN can be used in 5G networks, it provides a way to manage and automate network redundancy from a centralized control plane, circumnavigating major outages by determining optimal data flows in real time.