Infrastructure challenges wIth 5g

How to Manage the mmWaves and their Networks?

China Mobile, China Unicom, and China Telecom activated networks in less than five months after they were issued 5G licenses, across China. SK Telecom and Korea Telecom (KT) are the main competitors for the South Korean 5G market. Over 2019, EE, Vodafone UK, Three UK, and O2 UK launched commercial deployments in the UK. Vodafone Germany and Deutsche Telekom Germany launched 5G services in several cities of Germany during 2019. AT&T and Verizon are considered the 5G leaders in the USA.

The upcoming countries with 5G deployments include Switzerland, and the Nordic countries of Denmark, Finland, Iceland, Norway, and Sweden. In India, it is still some time away. The road to 5G is paved with infrastructure cost. There will be new spectrum, RAN

infrastructure, etc. And, even if the operators choose to delay the 5G investments, they would still need to increase the infrastructure spending to cope with their growing traffic.

Densification Improvements

Sanjay Bakaya, Regional VP, India & South Asia, Mavenir, said that 5G cellular technologies will provide consumers with data rates up to 10 times higher than 4G/LTE. The architectural requirements of 5G demands low latency for connected devices in time-sensitive areas. To meet this goal for effective communication, we require higher number of sites to be deployed over a smaller footprint, but connecting significant amount of devices. By providing larger number of sites with higher throughputs and low-latency communications, we can meet industrial

demands for critical applications like mobile robots, video surveillance, in-vehicle Infotainment etc.

Alok Kumar Sinha, Product Director, Network Analytics, Subex, said network densification gained traction since the promising growth of LTE networks. To cope up with the increasing number of mobile broadband data subscribers and bandwidth-intensive services competing for limited radio resources, the necessity of heterogenous network (HetNet) was considered by 3GPP, and standards in subsequent release, offering the key capabilities to support HetNet deployment were announced.

In HetNets, cells of different sizes, referred to as macro-cell and small cell (micro-, pico- and femto-cells), are listed in the order of decreasing base station power. The actual cell size depends on the eNB power, and on the antenna position, as well as the location environment; e.g. rural or city, indoor or outdoor.

In a Hetnet ecosystem, network densification with small cells are primarily added to increase capacity in hot spots with high user demand, and to fill in areas not covered by the macro network – both outdoors and indoors. They improve network performance and service quality by offloading from the large macro-cells. This results in a heterogeneous network with large macrocells in combination with small cells providing increased bitrates per unit area.

“5G cellular technologies will provide consumers with data rates up to 10 times higher than 4G/LTE. The architectural requirements of 5G demands low latency for connected devices in time-sensitive areas. To meet this goal for effective communication, we require higher number of sites to be deployed over a smaller footprint, but connecting significant amount of devices.” - Sanjay Bakaya, Regional VP, India & South Asia, Mavenir

Inspite of the standards and specifications made available by 3GPP to support HetNet in LTE network, HetNet deployments did not scale in volume. One of the primary reasons could be the continuous evolution and deployments of latest versions of LTE like LTE-advanced and LTE-Advanced pro.

Now, with the inception of 5G and its early implementations using a combination of 4G and 5G, mainly referred as non-standalone deployment (or NSA) brings network densification back into focus. Enhanced mobile broadband (eMBB) driven FWA (fixed wireless access) being the initial preferred application of 5G by many communication service providers(CSPs), fuel in the momentum to 5G network densification and make it more cost effective, with its support for mmWave, unlicensed access, integration with Wi-Fi, and RAN virtualization.

5G-driven densification encourages new business models. Some will involve the enterprise private networks. Some will be neutral host, small-cell deployments, where multiple operators share the network access infrastructure or, more commonly, the backhaul. One of the key benefits of 5G densification, in combination with LTE network, is the enhancement of customer experience,

as faster throughput data demand is skyrocketing at an exponential rate. So is the pressure on carriers to keep up and retain customer satisfaction, all, while containing costs and maintaining a healthy revenue profile.

It has become apparent that to stay competitive and meet high consumer data traffic needs, CSPs are finding the need to evolve their approach to providing mobile services. For CSPs to meet their goals, smallcell solutions come into picture to help mitigating costs and boost data traffic in the network. Another factor, which brings strong focus on 5G network densification is the fact that CSPs are thoughtful in how they deploy new network resources in a highly competitive industry where the return on investment (RoI) is an important consideration. Densification enable CSPs to provide “targeted services”, densifying their network with small-cells or providing fill-in coverage, where needed, for a fraction of the cost of deploying additional macro base stations.

Investing in New Equipment

How can operators invest in new equipment that would support spectrum bandwidths, laying fiber optics cables, and help in development of cellular transmission technology?

Bakaya of Mavenir said that the biggest challenge operators are facing with respect to 5G today, include:

• Spectrum availability and network deployment feasibility

Spectrum will remain a critical resource in 5G, and its availability and cost will have a major impact on a network operator’s ability to create a robust business case. The move from 4G to 5G will give rise to a large amount of new use cases. Their feasibility will depend heavily on the type and amount of spectrum network operators have or are able to secure in future auctions. That’s going to be a crucial factor in determining the subset of use cases each network will be able to economically support.

• Strategy use cases and business models

The operator will have to understand its DNA – i.e., the specific strengths and capabilities it possesses – as an essential step to determining the most relevant strategy, use cases and business model that they can support to accelerate the next generation of network growth. That understanding is also essential to predict the likely financial implications, including the pressures on traditional revenue, opportunities to find new models, and the investment required for the business and service strategy.

• Device innovation and technology breakthroughs

5G brings some considerable technical challenges that will require innovation and technology evolution. The move to 5G will herald the start of a new postsmartphone era, with a shift to purpose-built services delivered either through the IoT or surrounding the smartphone as part of a whole new world of devices. These will require specific product and technology strategies to support the new use cases they create.

• Network deployment approach

Once decided on a strategy for 5G, operators need to decide what their approach to network deployment needs to be. The deployment model and approach required will look very different depending on the spectrum networks have and the densification and coverage that they need for their target use cases. Use of mmW frequencies will require breakthroughs in network designs. 5G small cells will also require a new approach towards regulation and deployment planning.

“5G brings some considerable technical challenges that will require innovation and technology evolution. The move to 5G will herald the start of a new post-smartphone era, with a shift to purposebuilt services delivered either through the IoT or surrounding the smartphone as part of a whole new world of devices.”

• Architectural and platform innovation

New architecture and platforms will also be critical to support the deployment and operation of 5G in the RAN and core network. The choice of these will be largely driven by the concept of virtualization, and what level or type of cloud a network is implementing within its core network. Continuing to pursue disruptive technologies will be essential, and business success with network slicing will require a new operating model.

• Operational complexity

As they deploy their network, the ability to apply intelligence and automation to drive a leaner operational capability will be a crucial factor. Network and IT architectures merging, and end-to-end services-based operations predominating, will require a complete transformation of stacks, processes, people and automation.

Alok Kumar Sinha at Subex said that mobile backhaul is evolving from a static, linear connection to a programmable mesh interconnecting all mobile and cloud elements dynamically. The investment in transmission technology must evolve because the radio access and packet core elements it interconnects are changing to support new services and industry verticals. In the course of this evolution, traditional distinctions between fronthaul, backhaul, and backbone are blending toward an end-to-end common architecture.

In this evolution, open RAN (O-RAN), virtualization and multi-access edge computing (MEC) may be the factors that will have the largest impact on the transport infrastructure as we move to 5G. Not only do they alter how networks work, they disruptively change where and how network functions and content are physically located. This is a game changer for transport, because it alters what is being transported across various parts of the network, not just how much traffic or with how much latency.

This is a much deeper change, from a fixed, deterministic transport infrastructure to a flexible infrastructure that can reconfigure itself in real-time in response to traffic fluctuations.

While virtualisation and edge computing will change the wireline infrastructure, the 5G air interface will change its scale. 5G RAN will carry impressive amounts of traffic across the network, and will concentrate this traffic very tightly in dense hotspots

As 5G technology evolves, wireless networks will become more powerful, pervasive, dynamic and flexible. It will also become more complex and require more effort and more sophisticated tools to optimize the use of network resources. That’s where analytics, artificial intelligence, and automation come into play. It offers operators tools to manage complexity, and to benefit from the new capabilities and opportunities for differentiation and new revenue streams that this complexity brings.

In a 5G ecosystem, a CSP must plan its transmission network investments toward virtualization, MEC, O-RAN and advanced analytics tools for exceptional transport network management to offer superior services to its consumers and enterprises.

Operators going for low-band 5G spectrum

Some of the operators are also said to be opting for lowband 5G spectrum, instead of the so-called mmWave technologies. Bakaya of Mavenir said that demand for

than 4G LTE on existing bands, but not by a huge amount. 5G also is designed specifically to piggyback on the 4G network, with the aim of strengthening, rather than replacing 4G speeds. Eventually, like any wireless technology, it will become dominant as CSPs gradually upgrade their network towards much more consistently high speeds.

5G pioneers, AT&T and Verizon, used millimeter wave for their initial deployments. As Sprint and T-Mobile get into the game or make plans to do so, they have touted their ability to quickly cover broad areas by using lower-frequency spectrum. Although, that didn’t stop T-Mobile from spending more than $842 million to obtain millimeter wave spectrum in the recent auctions! Likewise, AT&T and Verizon expect to deploy 5G in lower-frequency bands, as well as in the millimeter wave band.

Verizon had amassed licenses for an average of 160 MHz of spectrum in all bands nationwide. In comparison, the company used four segments, apparently each comprised of 100 MHz, for a total of 400 MHz of millimeter wave spectrum to support its initial mobile 5G launches in Chicago and Minneapolis.

5G services will struggle to reach beyond urban centers and deep inside buildings without lower-spectrum.

The European Commission supports the use of the 700 MHz band for 5G services and in the United States the 600 MHz band has been assigned and T-Mobile has announced plans to use it for 5G.

“The ultra-low latency offered by 5G will power applications that are yet to be seen on mobile phones. With the processing power inching closer to edge, we will see mobile phones and other modern appliances perform at whole new levels in terms of efficiency, quality and consistency.” - Arun Kumar

VP, Network Solutions, CSS Corp.

Spectrum from 1-6 GHz offers a good mixture of coverage and capacity for 5G services: It is vital that regulators assign as much contiguous spectrum as possible in the 3.3-3.8 GHz range and consider the 4.55 GHz and 3.8-4.2 GHz14 ranges for mobile use. The 2.3 GHz and 2.6 GHz bands should also be licensed to operators for 5G use.

Spectrum above 6 GHz is needed for 5G services such as ultra-high-speed mobile broadband: 5G will not be able to deliver the fastest data speeds without these bands.

Arun Kumar, VP, Network Solutions, CSS Corp., said that opting for low-band spectrum enables communication operators to deploy 5G at a much larger footprint when compared to mmWave implementation. This band range is ideal in covering wide areas, both indoors and outdoors, with efficient connectivity and highly-reliable low latency communication networks. Low-band 5G spectrum is an optimal and cost-effective option for service providers who are deploying greenfield networks.

For instance, a network company based in the USA, is currently building a virtualized 5G network from ground up that aims to provide IoT connectivity and low-latency broadband service. Since their network equipment is based on Network Functional Virtualization (NFV), the opportunity for a lower cost deployment by implementing a low-band spectrum is significantly high. Additionally, the ability to create network slices brings in a new dimension of utilizing the same base hardware or setup, to create networks that are custom built for every situation (eMBB / eMTC / URLLC) thus, fueling cost efficiency.

Further Infra Needed?

It is said that despite 5G offering a significant increase in speed and bandwidth, its more limited range will require further infrastructure. Bakaya of Mavenir said 5G will initially use frequencies between Sub 6Ghz, ranging upto 300Ghz for wireless broadband communications and more, as the below Sub 6 Ghz frequencies are mainly used by the 2G/3G/4G technologies today. The advantage of using such high frequencies is that there is a lot of mmWave bandwidth available for new 5G services. It is much easier to develop massive antenna arrays as a reasonable size with higher frequencies. There are tradeoffs, because the signal penetration and range at 28Ghz or higher gets shorter and more subject to line-of-sight and foliage concerns.

For instance, 5G services are at range of upto 1,500 feet (500 meters) in line-of-sight with very large wall penetration losses, and generally, be targeted for hotspot deployments, not nationwide deployments. As a next phase, 5G will evolve to below Sub 6Ghz deployments to cover more wider areas and nation-wide coverage.

Arun Kumar of CSS, said that there are immense developments happening through 5G technology. However, the complexities that arise due to limited range is a significant challenge that is constantly being dealt with. To that end, service providers are working on overcoming this through a combination of measures:

• The providers are opting for Non-Standalone deployments ( 5G + 4G) that facilitates optimal coverage while providing required data rates.

• The providers utilize the mmWave technology that enables them to offer focused area coverage and high data rates needed for the urban and city center areas.

• Alternatively, the service providers also opt for lowband options of deploying 5G to enable extensive coverage with the tradeoff of lower data rates, but still significantly higher that 4G speeds.

Alok Kumar Sinha, Subex, added millimeter waves are wavelengths on the electromagnetic spectrum between 30 GHz and 300 GHz, allowing for high frequencies over narrow wavelengths signal degradation is one of the top challenges associated with 5G NR mmWave coverage rollout, with the environmental obstacles hindering 5G signal spread. Many of these obstacles have been addressed or are inconsequential for existing 4G networks.

Due to the associated multiple kind of losses it appears 5G small cell may need to be deployed on every city block in urban areas, to properly address the obstacles and the usage demands of a metropolis. To deliver full-bandwidth 5G NR using mmWave technology, engineers need to optimize antennas, components, power supplies, and microprocessors associated with small-cell distribution. Increased deployment of mmWave small cells will fill in major coverage gaps, bringing more intelligence to the network edge. This will enable the collection of more information about neighborhoods and the environment, and how users are moving throughout these spaces.

“Spectrum from 1-6 GHz offers a good mixture of coverage and capacity for 5G services: It is vital that regulators assign as much contiguous spectrum as possible in the 3.3-3.8 GHz range and consider the 4.5-5 GHz and 3.8-4.2 GHz14 ranges for mobile use. The 2.3 GHz and 2.6 GHz bands should also be licensed to operators for 5G use.”

With AI, ML and deep learning analyzing the data from these networks, operators will be able to make predictions and improvements to their coverage over time. These will allow 5G NR networks to become increasingly reliable over their lifespans.

Better 5G Antennas

Let us also look at how there will be better 5G antennae, to improve the coverage. Sanjay Bakaya of Mavenir said one important aspect of 5G is its ability to use mmWave spectrum from Sub 6Ghz and above to 100 Ghz, and eventually, higher. This differs from previous cellular technology deployments, in which lower frequencies had significantly better propagation cellular technology deployments, in which lower frequencies had significantly better propagation characteristics than higher frequencies.

5G can address such a wide range of spectrum, thanks to massive MIMO, which exploits the fact that in higher frequencies, wavelengths are shorter, and, at these higher frequencies, antenna elements can be closer to one another, resulting in more antenna elements. The greater number of antenna elements in higher bands enable more tightly focused beams that can compensate for the otherwise poorer propagation of the radio signal.

Industrial Cases of Ultra-Low Latency Apps

5G can also help in the industrial cases of ultra-low latency applications. Arun Kumar of CSS said the ultralow latency offered by 5G will power applications that are yet to be seen on mobile phones. With the processing power inching closer to edge, we will see mobile phones and other modern appliances perform at whole new levels in terms of efficiency, quality and consistency.

Alok Kumar Sinha of Subex said URLLC, or ultrareliable low latency, will guarantee latency to be 1ms or less. Low latency is important for gadgets that, say, drive themselves, or perform prostate surgeries. A study by Market Research Future found that the telemedicine market is expected to grow at a compound annual growth rate of 16.5% from 2017 to 2023, parallel with the emergence and roll-out of 5G. This means that faster network speeds and the quality of care will allow doctors to remotely engage with patients without the worry of network blackouts, disconnections, lag time.

Low latency allows a network to be optimized for processing incredibly large amounts of data with minimal delay (or, latency). The networks need to adapt to a broad amount of changing data in real time. 5G will enable this service to function. URLLC is one of the key enabling technologies in the fourth industrial revolution as well. In this new industrial vision, industry control is automated by deploying networks in factories. Typical industrial automation use cases requiring URLLC include factory, process and power system automation.

Bakaya of Mavenir said that a growing number of mission-critical applications have stringent communication performance and reliability requirements. Communications with vehicles, high-speed trains, drones and industrial robots are a few examples of applications where wireless must meet either high reliability (for example, <10-5 packet drop rate) or low latency (for example, ~1 ms) requirements, or both simultaneously.

These applications frequently have strong security requirements. To meet these, 5G combines URLLC with enhanced Mobile Broadband (eMBB) services under a unified 5G air interface framework. To achieve 1-millisecond goal, a basic problem that needs to be addressed is end-to-end network latency.

This is the time period from when, for example, an Internet of Things (IoT) sensor transmits data to the point that processing is complete at the back end of the network, and the subsequent communications are generated by the network in response and received at the sensor. URLLC shortens by reducing the user plane latency through communication from application processing at device modem to the application processing in base station modem.

Standards and Spectrum Issues

Finally, let us look at how crucial will be standardssetting and spectrum allocation for 5G networks. Bear in mind that 5G networks have not even started in some parts of the world, though. Alok Kumar of Subex said one needs to consider that as 5G networks are likely to be heterogeneous. 5G standardization process is complex and highly innovative. Relevant standards bodies, both regional and global, have set out timetables for their work. These timetables are significant in the development of 5G, even though the industry is likely to agree on working definitions of 5G, ahead of standardization.

For governments and CSPs, spectrum is an incredibly valuable asset. Companies spend, and subsequently, governments are now earning, billions of dollars to get access to particular sets of frequencies. For example, it’s common to hear about auctions for potential 5G spectrum where CSPs will bid enormous amounts of money to get access to the frequencies, they want to help build out overall coverage maps and performance capabilities.

A few other important things to understand about spectrum are that buying it is only the first step. You still need to purchase the appropriate network infrastructure equipment, tuned to transmit and receive at the correct frequencies, and install it, before you can launch a 5G service.

Another key area URLLC can empower is by bringing several technological transformations in the transportation industry, including automated driving, road safety and traffic efficiency services. These use cases will require information to be transmitted among vehicles reliably within extremely short time duration. Several applications and use cases are already under research and development, the most promising one being automated driving.

URLLC is, arguably, the most promising addition to upcoming 5G capabilities, but it will also be the most challenging to secure. URLLC requires a quality of service (QoS) totally different from mobile broadband

services (eMBB). With 3GPP release 16 scheduled for final release in June 2020, it will be interesting to see the enhancements and key feature sets made ready for commercial purpose.

Sanjay Bakaya of Mavenir concluded the standardsetting process is important because it will determine not just how 5G networks are built, but also how money flows between participants in the 5G ecosystem. The 5G standards suite will build on existing 4G LTE standards and provide flexible interoperability for the various flavors of 5G with legacy 4G and 3G systems (which will continue to operate for some time, particularly in developing market countries).

“One needs to consider that as 5G networks are likely to be heterogeneous. 5G standardization process is complex and highly innovative. Relevant standards bodies, both regional and global, have set out timetables for their work.”