5G – What, Where, When and Why

Nighttime cityscape overlaid with glowing digital icons and lines representing a network, prominently featuring "5G" connectivity symbols floating above the skyline.

5G has been getting a lot of press exposure, although it has been under development for many years, even as 4G and 4G Long Term Evolution (4G LTE) were still being rolled out. To put this evolution into perspective, it took about 25 years to go from first generation analog cellular (1G), introduced in the eighties, to the move to digital: 2G, 3G and then to 4G, which was introduced in 2010 in the US.

In a way, this virtually mirrors the evolution, user experience, growth and adoption rates of the Internet. In effect, the increase in bandwidth, coupled with cost reductions, fostered and enabled the momentum of mass adoption, as we progressed from the boing-boing sound of dial-up modems to the first 1 megabit DSL “broadband” connection (over twisted copper analog phone lines), to the gigabit level fiber optic services currently offered to home users. With each generational technology performance step, bandwidth costs continued downward, further driving user Internet adoption.

4G Reaching Capacity

It has been almost a decade since the first 4G cellular services were rolled out and became commercially available in the US and provided the step-up in bandwidth from 3G to support the myriad of applications that we now take for granted on our “smartphones.” The enhancement of 4G LTE provided a relatively good platform to support even more applications, including the delivery of good quality streaming video at sufficient resolution for most devices (phones, tablets, and laptops). Nonetheless, users always expect ever greater performance from their devices, as well as more bandwidth from the wireless network. Moreover, the increasing number of smartphones, combined with their applications’ constant always-on, background data demands, has grown to the point where 4G LTE has effectively reached the limits of its data channel density and capacity. This is especially true in dense urban environments which have many more connected devices than suburban and rural areas.

The Frontier of 5G

We now stand at the threshold of the next (but far from final) frontier of 5G. The general public hype at this juncture is mostly being driven by smartphone makers in conjunction with the wireless carriers, just as it was when 3G was transitioning to 4G. However, unlike the step-up from 3G to 4G, phone users will not see the full effect of the promised “quantum leap” in bandwidth that 5G offers over 4G. Initially, 5G will be a marketing feature aimed at motivating users to upgrade to newer ever “faster” smartphones offering greater raw bandwidth (10-100X increase over 4G), and it also promises much lower latency, with the expectation of going from 50 milliseconds down to 1 millisecond.

Yes, users will certainly be happy to download a movie in 10 seconds instead of 10 minutes, and it will also make the user’s phone touchscreen experience feel more responsive. Nonetheless, why is there so much effort and investment being put into the development and deployment of 5G networks? The main long term strategic benefit of 5G capabilities will be enhanced device-to-device communication.

5G May Be The Accelerator for Smart Cities

At present, 4GLTE is reaching its technical limits in several areas; raw speed, channel density, bandwidth per channel and latency. 5G is envisioned as a much broader platform to support, and be the core foundation for, the industrial applications and services foreseen for the next decade.

5G architecture encompasses a variety of applications and communication endpoints which go far beyond just existing user-held mobile devices. We now need to think in terms of millions (perhaps billions) of fixed devices, such as a wide variety of sensors in Smart Cities or “Connected Communities.” On the other end of potential 5G applications are self-driving vehicles and other autonomous devices. They will require very-low latency approximating near real-time connectivity capabilities. This includes direct device-to-device communications as well as device-to-centralized control, which are just some of the many technical challenges that 5G was designed to meet. The theme of MWC Barcelona (formerly Mobile World Congress) which took place in February 2019 was “Intelligent Connectivity.” It covered an extensive range of topics and presentations, ranging from how 5G can enable AI and robotics for “Smart Communities” which included concepts such as robotic mowers to help smart cities and smart gardens become more sustainable.

These capabilities, and the multitudes of others that would be found in a “Smart City” will require a plentitude of short-range “small cell” millimeter-wave (mmWave) radios. These could be installed on streetlights, telephone poles, utility poles or lower rise building rooftops. This is in comparison to the taller towers or high rise buildings which would be used for greater distance coverage by high-powered macro-cells because of the propagation characteristics. In many situations, the macro-cell would coexist in many of the same locations with current 4G systems.

5G to the Home

Another aspect of 5G is fixed wireless to the home. Some service providers are considering this facet of 5G as a cost-effective way to displace and avoid the cost of adding new or additional wiring (coax or fiber), as the transport medium to home users. For example, Sprint states that it plans to begin its mobile 5G rollout in the first half of 2019, including some of the largest cities in the country: Atlanta, Chicago, Dallas Los Angeles, and New York City. Conversely, AT&T indicates that it is beginning to offer a 5G fixed Wireless service to rural households and small businesses, via an outdoor antenna and indoor Wi-Fi Gateway router. This would eliminate the need to string last mile cables to home customers, a capability that AT&T or Sprint does not have. In contrast, Verizon has extensive hardwired distribution and last mile fiber networks to the home for phone, Internet and cable TV. Yet, Verizon Wireless is also currently introducing its 5G wireless service to the home, but initially in major cities; Houston, Indianapolis, Los Angeles, and Sacramento. That makes this implementation very interesting since Verizon is already well entrenched in urban areas. This could be because moving forward, they may see 5G as a more cost-effective way to add new customers via the same nodes and avoid the installation and maintenance costs of expanding their fiber network in cities, or by utilizing 5G small cells as a distribution mechanism inside of large apartment buildings.

The Development of 5G Technologies and Specifications

The 5G architecture is composed of a number of multi-layered intertwined technical elements that are still evolving, under a broad umbrella of organizations, concurrently being developed domestically and internationally, with the ultimate goal of global interoperability. Here are some of the organizations involved in the development of 5G standards, as well as industry associations:

Standards Bodies and Industry Organizations

  • ITU International Telecommunication Union
  • 3GPP 3G Partnership Project
  • ETSI European Telecom Standards Institute
  • IETF Internet Engineering Task Force
  • FCC Federal Communication Commission
  • IEEE Institute of Electrical and Electronics Engineers
  • TIA Telecom Industry Association (US based)
  • CTIA which represents the U.S. wireless communications industry

While this is only a partial list, one of the central international organizations is the International Telecommunication Union (ITU), which has already created a 5G technology roadmap.

Comparison of expected performance increases of 5G vs. 4G-LTE

Performance CategoryLatency Device-DeviceThroughputConnection Density(per square km)
5G1 ms10 Gbps1,000,000
Improvement Factor30-50X100X100X
4G-LTE30-50 ms100 Mbps10,000
Mobile and Fixed Wireless

The ITU 5G/ITM-2020 specification is subdivided into two frequency bands, FR1 (<6 GHz) and FR2 (24.5-52.6 GHz) mmWave. Short range “Small Cells” and “Spot Cells” provide coverage on the ground level and within buildings, and can also intercommunicate with higher power “Macro-Cells” that provide wide area coverage.

While this sounds somewhat simple in concept, there are numerous technical issues and interconnected sub-components that create the 5G Radio Access Network (RAN) infrastructure. The small-cell mmWave radios are coupled to Distributed Antenna Systems (DAS) to provide “last meter” transport that supports end-point devices. There are three types of DAS designs: passive, active and hybrid. The passive DAS is just an antenna, connected by cable and driven by the small cell radio. The active DAS contains radio electronics to amplify the signal to provide greater coverage – which requires power. The hybrid DAS combines both to offer more cost-effective coverage,

At ground level, numerous small-cell mmWave/DAS mounted on street poles will be vital to providing ultra-low latency connectivity (and mesh interconnectivity), to enable autonomous vehicles and other applications. However, the mmWave signals have very little penetration into concrete and steel buildings.

Since ground level 5G small-cells will not be able to support 5G devices in large high rise buildings, indoor small-cell radios with hybrid DAS systems will need to be installed for in-building coverage. WiFi networks are prevalent in commercial spaces for wireless data to user devices. Eventually, it may be more cost effective to use these 5G-DAS systems to augment or perhaps supersede traditional WiFi. The in-building small-cells could connect wirelessly to the Macro-Cells, or in some cases, fiber may also still be used as the vertical backbone to ground level connectivity to the telecom network.

Implementing and Deployment of 5G Infrastructure

Even while 5G roadmap specifications continue to be developed, wireless communications systems are regulated by each country’s government. In the US, the Federal Communications Commission (FCC) controls and issues the regulations. For 5G to proceed in the US, there are several vital elements that need to be addressed:

FCC Allocation of Frequency Spectrum
The current FCC policy is focused on supporting and accelerating 5G. This is a critical issue for overcoming federal regulatory impediments to deploying the range of new frequency spectrums that are needed for 5G deployment.

List of Frequency Spectrums posted by the FCC as of March 2019:

Frequency SpectrumFCC Description and Status
High-band:The FCC held its first 5G spectrum auction in 2018 in the 28 GHz band. In 2019, the FCC will hold an auction in the 24 GHz band starting on March 14 and auctions in the upper 37 GHz, 39 GHz, and 47 GHz bands later in the year. With these auctions, the FCC will release almost 5 gigahertz of 5G spectrum into the market-more than all other flexible use bands combined. And we are working to free up another 2.75 gigahertz of 5G spectrum in the 26 and 42 GHz bands.
Mid-band:Mid-band spectrum has become a target for 5G buildout given its balanced coverage and capacity characteristics. With our work on the 2.5 GHz, 3.5 GHz, and 3.7-4.2 GHz bands, we could make up to 844 megahertz available for 5G deployments.
Low-band:The FCC is acting to improve the use of low-band spectrum (useful for wider coverage) for 5G services, with targeted changes to the 600 MHz, 800 MHz, and 900 MHz bands.
Unlicensed:Recognizing that unlicensed spectrum will be important for 5G, the agency is creating new opportunities for the next generation of Wi-Fi in the 6 GHz and above 95 GHz band.

Beyond the FCC approval of frequency spectrum for 5G radio equipment, they must also be able to be installed and coexist on the same towers or rooftops without interfering with existing 4G LTE services. In addition, the hundreds of thousands of small-cell mm-wave radios installed on light-posts, electrical and telephone poles will require approvals by multiple town, city, county and state agencies, as well as the various entities that own the poles and rights of ways.

FCC Infrastructure Policy

To speed up approval rights of installing radio equipment on municipal light poles (as well as telephone and power poles and the installation of new small cell sites), the FCC has reformed previous rules to accommodate small cells. The reforms ban municipal roadblocks that have the effect of prohibiting deployment of 5G and give states and localities a reasonable deadline to approve or disapprove small-cell siting applications. It should be noted that this new policy is being challenged by some states, city, and local governments, since they usually review and grant service providers the rights to install their equipment.

What are 5G Strategic Vectors and Use Cases?

Unlike 2-3-4G network rollouts, which were primarily driven by providing better service and faster data to typical user devices (phone, smartphone, tablets, etc.), much of 5G’s capabilities are designed to deliver a more comprehensive portfolio of services (applications) and support the massive number of IoT devices to enable “smart cities”, autonomous vehicles and devices, (self-driving cars, buses, trucks, drones, robots, etc.).

5G will also enable vertical applications that are not technically feasible or economically justified today using 4G technology, including:

  • Drone powered by edge compute: The Verizon and Ericsson Distributed Edge Cloud amplify the power of simple drones to match or exceed the capabilities of complex drones, which are much more expensive. This proof of concept demonstration shows that as intelligence and processing are moved to the 5G core and the very edge of the network, existing device constraints will be lifted, enabling advanced applications with low-cost devices.
  • Augmented Reality, Virtual Reality, and Immersive Experiences: 5G’s low latency and high bandwidth will enable ultra-realistic high-definition video without the lag associated with 4G. This can be utilized for commercial and industrial applications, such as augmented technical support or remote control of robots. It will enable enhanced consumer applications for entertainment and gaming, as well as for education.
The 5G Ecosystem

The 5G landscape obviously encompasses the major wireless telecommunications service providers; it also will be driven by the smartphone and other endpoint device manufacturers. However, they, in turn, will rely on the continued development of the underlying communications technology and network equipment providers such as Cisco, Ericsson, Intel, LG, Nokia, Qualcomm, Samsung, as well as many others. While 5G enhanced network capacity and performance may be the enabler of Smart Cities and all that implies, they will also require mass amounts of data processing and storage. Therefore, another critical element of the ecosystem will be data centers. What will define a data center in the 5G era?

Data centers are now beginning to consider and anticipate the change of where data processing, storage will need to occur. They are also examining how much network bandwidth will be required between 5G nodes and “edge data centers” as well as network connections to smaller regionalized and central data centers.

Data Centers Reimagined

Previously the wireless carriers were the nexus of connectivity, but in most cases were only a gateway to user-focused applications and the data hosted in data centers. In contrast, 5G will change the dynamics of that equation. This will change both the technical demands and the business models of the carriers, the enterprise, colocation and cloud service providers. These technological and business changes will impact the location, size, and functional focus, as well as inter-connectivity and data storage requirements of data centers. This metamorphosis will result in the need for greater infrastructure flexibility to adapt to a changing computing and communication architecture, which could impact the network, processing and even the storage architecture.

What defines a data center? Is it merely a physically secure building designed to support IT equipment with conditioned power and stable environmental? 5G may also help accelerate the blurring of the classic categories and definitions of IT infrastructure; Compute, Storage and Network, a trend that is well underway with the virtualization of all of typical components associated with those functions: Servers, Storage Systems (disk devices/arrays) and Network Equipment (Switches, Routers, Firewalls, etc.). The last few years have brought about a reimagined IT architecture featuring a software-defined infrastructure included:

  • Software Defined Data Center (SDDC)
  • Software Defined Network SDN
  • Network Functions Virtualization (NFV)
  • NFV Infrastructure (NFVI)

All of the above are intended to reduce dependence on single-purpose appliances by taking functions that were previously built into hardware and implementing them in software that runs on industry-standard servers, network, and storage platforms and to be resources across single or distributed data centers or telecommunications systems. Much of this is being developed as open source consortiums, such as the Open Compute Project (OCP) hyperscale members, as well by Open Networking Foundation (ONF) telecom service providers, as well as other organizations. The vested interest and common goal is to reduce hardware costs and increase flexibility, as well as interoperability.

The existing 4G wireless networks primarily deliver data to a user’s mobile device (phone, tablet, etc.), that was stored in a dedicated data center or from cloud storage service (contained in one or more data centers) typically over Internet backbone peering points. At this juncture, a great deal of the traffic may consist of streaming content, videos, music, etc. Moreover, while the network also allows uploading data (photo, videos, etc.) from the millions of user devices, overall wireless network traffic is typically asymmetrical; more traffic flows from central resources to mobile devices than the reverse. 5G will change how and where the computing occurs, and resultant data is stored, transported and the ensuing information delivered to the end-user (or device).

Presently, there is very limited or no connectivity or data traffic directly between users’ mobile devices. One of the key aspects of 5G is to enable low latency communications between a myriad of IoT devices. It is also one of the key enablers of the self-driving vehicles and other autonomous robotic devices, which require intercommunication, as well as centralized connectivity. While a lot of onboard processing will need to occur in self-driving vehicles, a massive amount of 2-way data will also need to be communicated between vehicles to ensure synchronization. In effect they will no longer become just endpoints; the vehicles will become part of a moving 5G mobile mesh computing network.

The Edge Data Center

Some 5G Macro-Cell nodes may need to act as or be combined with a micro or edge data center. While conceptually similar to the small telecom shacks which contain the radio equipment at traditional cell towers, they will have additional requirements. In many situations, they will need to be condensed into small weatherproof self-contained enclosures, designed for operation in remote locations. However, since they will also contain IT equipment to process data, as well as high-speed solid-state storage, they will need more power than radio-only cell sites. Therefore, edge data centers will require UPS, cooling, and power back-up systems that most radio-only cells sites do not typically contain. Redundancy, such as N+1 or 2N power will be essential, as well as extensive remote monitoring of critical infrastructure systems.


So with all the promised benefits of 5G, when will they become a reality? The marketing departments of wireless service providers and smartphone manufacturers are all busy pushing the hype envelope. For example, Verizon Wireless proclaims 5G as the “4th Industrial Revolution” on their website, the others being Personal Computers, Electricity, and Steam. While 5G will undoubtedly have many benefits, not everyone would agree it rates the same revolutionary impact of those major milestones.

The carriers already have huge investments in the existing 4G infrastructure, and they are driven by customer revenue. At the moment, the competing US carriers’ smartphone 4G service plans have bundled data plans into a relatively fixed monthly price. This seems to meet most existing applications and will continue to do so for a while for most subscribers. Most smartphone manufacturers promise new models with 5G capabilities sometime in 2019. However, they will be at the top end of the price range, so only the early adopters will buy them initially. Moreover, the 5G service plans are more expensive at the moment, and the various carriers will only have limited 5G coverage in a few test market cities.

Moreover, since increased channel density and throughput is a significant benefit, 5G deployments will initially be concentrated in dense urban environments. If the early performance reviews and area coverage in those test areas are positive, many industry observers believe 2020 will be the first year for 5G handsets and additional service coverage. However, the rate of substantial conversion of 4G to 5G of smartphones will take multiple “2-year” phone refresh cycles, since the majority of mainstream users are relatively satisfied with existing 4G LTE speeds and many would be willing to wait for lower cost phones.

According to a February investor’s conference press release, Verizon plans to launch its 5G Ultra Wideband Network in more than 30 U.S. cities in 2019. Verizon 5G Mobility will launch in the first half of 2019, and Verizon 5G Home will expand coverage to more markets in the second half of 2019. Revenues from 5G Mobility and 5G Home will begin to scale next year and are expected to contribute more meaningfully to growth in 2021. The company’s Mobile Edge Computing platform, which will enable real-time enterprise applications, is expected to launch in fourth-quarter 2019.

5G will enhance many of the consumers’ smartphone experiences and applications; however the 5G client will no longer be primarily a user’s smartphone, IoT devices will far outnumber them. The bigger question is what “killer application” for IoT or Industrial IoT (IIoT) devices – that can only be supported by 5G’s low latency or higher channel density and throughput – would justify the carriers to make a sizeable financial commitment to wide-scale deployment.

Hyperscale cloud service providers will also play an increasingly important role as 5G applications develop. While 5G may be the communications enabler of the Smart City, Artificial Intelligence (AI) and Machine Learning (ML) will be integral to the fulfillment of things like the Smart Cities vision and will require mass amounts of back-end data processing and storage.

In the end, regardless of the application, 5G will change the relationship and resource capabilities of the various stakeholders. This will require mutual technical coordination and evolution of the relationship between the wireless service providers, and data center cloud and colocation providers. This will also continue to evolve as the CapEx and OpEx of competing business roles, goals and investment justifications mature.