Vertiv Guide to 5G Technology

5G networks will be far denser than existing 3G and 4G networks in order to deliver on the dual promises of increased bandwidth and lower latency. That means there will be far more cell sites across the network and each site will feature more IT equipment. These are significant differences. Operators aren’t just adding to their existing networks; they are building new networks on top of those 3G and 4G architectures.

These differences manifest in various ways. The addition of IT equipment across the network requires greater attention to environmental protection of those sensitive electronics. That means hardened cabinets and enclosures and dedicated cooling and humidity control. Precision cooling typically was unnecessary in all but the most extreme climates in traditional telecom networks as those networks – including 3G and 4G iterations – required minimal IT equipment in the access space. Not so with 5G.

The widespread introduction of IT systems across the network introduces another complication. IT equipment requires a lot more energy to run and therefore typically operates on AC Power, whereas existing telecom networks and equipment rely on DC power. Additionally, alternative energy sources are used to supplement network power in many parts of the world, and those sources also produce DC power. This divide can be bridged, but it requires the right partner. Vertiv has deep, unique expertise in both the IT and telecom spaces that can help operators navigate what can be unfamiliar power architectures.

This addition of IT and introduction of AC power has been happening in central offices for several years and continues today. The access space is the new frontier of 5G with cell tower sites undergoing significant changes or upgrades to support 5G and these new IT resources. These sites have cycled through multiple architectures, from RAN to D-RAN to C-RAN toward what ultimately will be Cloud-RAN, or basically a virtualized cellular network that shifts loads seamlessly across sites and geographies.

These architectures have evolved to support the demands of the network, moving equipment from the ground to the tower and from the base of the tower to centralized hubs based on bandwidth and latency requirements.

The early macro base station with radio access network (RAN) architecture consisted of a cell tower and antenna with all associated equipment at the base of the tower connected to the antenna via coaxial cable. These types of sites required multiple enclosures or sometimes larger shelters housing all the required equipment.

Distributed radio access network (D-RAN) moved the remote radio heads (RRHs) from the base of the tower to the top of the tower alongside the antenna and replaced the coaxial cable with fiber. The rest of the equipment remained at the base. D-RAN reduced the power required, and increased network capacity, by reducing the distance between the antenna and the radio (reducing signal loss). The use of RRHs on the tower also meant a smaller equipment footprint at the base of the tower.

The more recent move to centralized radio access network (C-RAN) has been more disruptive. C-RAN architectures emerged to support 4G and took equipment from the base of the tower and centralized it elsewhere to serve multiple sites. This reduced the physical footprint at the tower and provided other benefits related to equipment monitoring and service. Many current 4G sites employ C-RAN architectures, but the move to 5G requires another re-evaluation of cell site design.

Again, the promise of 5G is based on the ability of operators to place computing as close to the consumer as possible, starting where they already have access to real estate – at cell tower sites. C-RAN has been removing computing equipment from those sites. We’re not going to see an immediate reversal – those centralized C-RAN sites will play a role in 5G – but we will see more IT equipment returning to those tower sites, the introduction of the open radio access network (O-RAN), and a brand new set of deployment challenges.

There is a tendency to think about 5G as it applies to existing cell tower sites, and that certainly is one front in the ongoing global deployment campaign. In reality, however, 5G deployment is happening in central offices, in greenfield cell sites, and in IT deployments at the edge of the network. 5G networks are far denser and more complex than previous generations, and deployment is every bit the challenge that suggests.

In the central office, that means retrofitting existing facilities to support the IT servers required for 5G traffic. Traditional central offices were switching centers running exclusively on DC power and with a heat load of 2-3 kW that required little attention to cooling. 5G is changing everything. Those copper cables and line switches are out, replaced with racks of servers, additional DC power systems and/or AC UPS systems, and precision cooling units to manage the corresponding heat load.

These have been fundamental differences between telecommunications and IT architectures for decades. Telco relies on DC power to run the network and requires minimal cooling. Data centers and IT facilities use AC power to run servers, and the electronics in those servers are more sensitive to heat and require more sophisticated cooling to function properly.

With 5G, those lines are blurring. More IT equipment is being introduced into traditional telco environments, completely changing the power and cooling profiles for those facilities. In most cases, it’s not as simple as either AC or DC power. These facilities are evolving to include both, and that requires a special expertise to install safely and manage effectively. Vertiv, with decades of experience in both telecom and data center infrastructure support, has solutions for both AC and DC environments and is equally adept with both architectures.

The most common approach is a blend, still leveraging DC power systems for some elements of the facility while adding AC UPS systems for backup power to the servers. One trend emerging in all cases: the introduction of precision cooling. This is necessary to cool the IT equipment, but it adds additional equipment to the power load. This is one reason why, even though 5G is more efficient than 4G on a per-gigabyte basis, overall energy consumption will be much higher with 5G.

SmartRow and SmartAisle, although originally designed for data center environments, can be configured to support these blended AC/DC environments, although those AC and DC pods most often are separated for safety. In central offices, SmartRow and SmartAisle typically are deployed with 10-20 racks and incorporate hot- or cold-aisle containment for energy efficiency.

Supplementing this traditional core/access model is an emerging edge of the network that is necessary to support 5G. These edge resources add additional computing closer to the end user, which is necessary to enable the low-latency, high-bandwidth applications made possible by 5G. These resources can be deployed at tower sites or elsewhere in the access space.

The proliferation of the edge has been happening on the data center front for several years, and now telecom operators are deploying their own edge computing resources and, in some cases, leveraging existing edge computing/cloud providers to meet their 5G needs.

These edge data centers are sophisticated and critical to delivering full 5G functionality. The Vertiv™ SmartMod™ is a modular solution to this need, typically deployed as a 100 kW data center, with up to 10 racks at 10 kW per rack. The SmartMod features separate rooms for IT equipment and power systems and batteries and includes thermal management for all systems.

If it sounds like 5G requires expertise beyond what has been required of telcos in the past, that’s because it does. These 5G networks are a hybrid of telco and data center resources, blending AC and DC equipment and architectures in ways unfamiliar to most operators. Expertise in both arenas is critical to optimize 5G deployment.

Vertiv is singular in its knowledge and experience in both data center and telecom equipment and architectures. We are supporting these converging industries with unmatched expertise and seamlessly integrated solutions, removing these unfamiliar obstacles for operators with no time for a learning curve.

5G is forcing changes to the access network that are nearly as drastic as those seen in the central office. The base stations at cell tower sites support a load of about 5 kW at a standard 3G or 4G site. With 5G, those loads are 20-40 kW. That sort of massive increase in power and computing requires significant upgrades to existing sites.

Managing the limited real estate at these sites is the first consideration, and that was one driver for moving radios to the tops of cell towers, and those towers now can hold dozens of radios. In some cases, rectifiers are placed on the towers as well, allowing the operator to run AC power up the tower, which provides cost savings because AC cable is less expensive than DC cable.

5G may be a global technology, but deployment is not happening at the same pace or in the same way around the world. China and South Korea sprinted out ahead in the race to 5G, pulling the rest of the Asia Pacific region with them.

Operators in that part of the world have been faster to deploy new networks and network equipment, performing site upgrades as needed and as a complement to an aggressive rollout of new sites. They also have been more open to high-voltage DC architectures, which is unsurprising considering many of the adopters of that technology in the data center were located in the region.

The strategy in the U.S. has been slightly more conservative than what has happened in Asia, with site upgrades from 4G to 5G playing an important role. There have been differences across providers, with the largest operators choosing to deploy to meet current and future needs and smaller operators opting for smaller deployments to minimize capital investment.

The surprising outlier is Europe, where 5G rollouts lag Asia and the U.S. by about a year. There are a number of ongoing issues, starting with continued delays in assigning frequencies on the spectrum.

There are some notable exceptions – France and Finland moved early and received spectrum assignments quickly – but in most cases auctions for space on the spectrum haven’t happened yet. The expectation is that some 70-80% of those assignments could happen by the end of 2021.

The sluggish start should not be mistaken for a lack of activity in Europe. The early movers are progressing at a brisk pace, and even operators still waiting for those spectrum auctions are heavily engaged in site prep so they can move quickly when the time comes.

Many European operators are selling their cell towers back to tower companies to raise the capital needed for 5G investment. Then they are turning around and leasing the use of those towers from the tower companies.

This is creating a need for intelligent power management at those sites, so operators are charged only for the time use at a given tower. Vertiv has power metering and management solutions for these multi-tenant arrangements.

Europe also has regulations around the number of cell towers that can be deployed, so the densification of the 5G network there is happening in different ways. To overcome the lack of towers, operators deploy a lot of overlapping small cells. These overlapping designs allow operators to deploy some sites without backup power, opting instead to shift loads to an overlapping site.

One surprising issue in Europe: ensuring 5G networks can support voice communications. Some 4G networks in the region are not equipped to support voice calls and instead rely on legacy 2G and 3G networks. The early indication, however, is that many operators plan to decommission those 3G sites and keep the older 2G for voice transmissions.

The slower rollout across Europe has afforded operators time to focus more on the energy consumption, emissions, and overall environmental impact of their networks. These issues are prioritized across the continent regardless of energy, but telcos there are aware of the issues inherent in 5G.

European telcos have long embraced hybrid power systems and are expected to continue to do so to support 5G and minimize the carbon footprint of those networks.

As expected, investment and progress in the Middle East and Africa has been centered in wealthier countries and urban centers.

Delivering exponential increases in the speed and volume of data transmission, 5G networks will open the doors to countless new, advanced, and increasingly valuable applications across all walks of life. As we come to rely on these applications, the reliability and security of the network becomes even more critical.

This presents an unprecedented challenge for today’s telecom operators, who must upgrade hundreds of thousands of existing sites, build just as many new sites, and manage the massive spike in energy consumption that will come with the proliferation of IT systems across the network.

That widespread introduction of IT in the telecom space is the central issue in terms of powering and protecting these 5G networks. Adding IT in the core, access and at the edge means adding AC power in traditionally DC-powered environments, and that is a foreign concept to most telcos. Their expertise in DC power goes back more than a century, but AC is new, different and adds a complication they can’t ignore.

The model emerging is something of a hybrid of traditional telco and data center architectures. Vertiv, with unique expertise across both industries, is working with operators around the world to deploy infrastructure solutions that support these sometimes-opposing interests and ensure their 5G networks operate reliably and efficiently.