5G NR mmWave and Deployments

- 5G Deployment

5G comes in two flavors. One utilizes the sub-6 GHz band, which offers modest improvements over 4G LTE. The other utilizes spectrum above 24 GHz, ultimately heading to millimeter-wave (mmWave) technology. As a general rule, as the frequency goes up, so does the speed and the ability to carry more data more quickly. On the other hand, as the frequency increases, the distance that signals can travel goes down. The result is that many more repeaters and base stations will be required.

Unlike previous generations of technology, 5G adoption likely will be a mix of technologies that will evolve over a long period of time. So while the rollout of was relatively quick, 5G handsets and base station coverage outside of cities could take decades. In fact, it’s not clear if this technology will ever be universal.

- Leveraging the Potential of 5G Millimeter Wave

Millimeter Wave (mmWave) boosted networks are taking off globally, delivering multi-gigabit speeds, capacity and exceptionally mobile broadband speeds in suburban and rural communities, thanks to extended range software.

While some communication service providers still wonder if there is a place for the high band (millimeter wave, or mmWave) as a mainstream 5G technology, others are already harnessing the opportunities it presents. In combination with established solutions, like fixed wireless access, largely untapped millimeter-wave frequencies can help meet the increased global demands for high-quality connectivity – as well as facilitate exciting new use cases.

Since its initial rollout in 2019, service providers across the globe have hurried to have their networks 5G enabled and become the first 5G players in their respective markets. Many are now reporting that the mission-critical capabilities of 5G, such as superior speeds and low latencies, are quickly expanding the number of use cases and intensifying demands for data and performance. 

- 5G Standardization To Provide Connectivity For Services With Extreme Requirements.

When the 5G standardization process began, certain requirements were identified to provide connectivity for services with extreme requirements on availability, latency and reliability. These include enhanced mobile broadband services to smartphones and other mobile devices for video streaming via social media and realtime online gaming:

• 1,000 times higher data volumes
• 10-100 times more connected devices
• 10-100 times higher typical userdata rates
• Five times lower latency

In response, 5G radio frequency ranges were widened to meet the need for enhanced data and performance. They now include all those previously held by 4G, as well as more frequencies up to 6GHz (Sub-6) and the high band (mmWave) spectrums. 

The Sub-6 5G capacity could theoretically run out in mature markets by 2023 as a direct result of the rise in data consumption. This would effectively make 5G mmWave a valuable resource for the continued offering of enhanced mobile broadband services .

- 5G mmWave Deployments

As user demand continues to rise, LTE will be unable to provide enough capacity and 5G will become dominant. Initial outdoor capacity from macrocellular sites running 5G New Radio (NR) over the lower frequency bands will be supplemented by 5G mmWave, which is needed to deliver the 5G promise of super-fast data rates of more than 10 Gbps and ultra-low latency of around 1ms. 

The spectrum for 5G services not only covers bands below 6 GHz, including bands currently used for 4G LTE networks, but also extends into much higher frequency bands not previously considered for mobile communications. It is the use of frequency bands in the 24 GHz to 100 GHz range, known as millimeter wave (mmWave), that provide new challenges and benefits for 5G networks. mmWave bands extend all the way up to 300 GHz, although the 28 GHz and 39 GHz bands are likely to be the most used initially. The available spectrum for mmWave, the supported bandwidths, and how antenna technologies work together to deliver multiple Gigabit data rates to end users are  part of the 5G revolution. 

Previously, the use of frequency bands much above 6 GHz was considered unsuitable for mobile communications due to the high propagation losses and the ease with which signals are blocked by not only building materials and foliage, but also by the human body. Although these challenges place limitations on mmWave deployments, new antenna technologies together with a better understanding of channel characteristics and signal propagation enable a number of deployment scenarios to be considered. 

[San Francisco, Califonia - Civil Engineering Discoveries]

- The Deployment of 5G mmWave Small Cells

The high penetration losses and blocking mean that mmWave deployments will cover outdoor or indoor environments, but not provide outdoor to indoor connectivity. The mmWave cell sizes will, therefore, be smaller and higher in density. Also, it can be expected that mmWave will coexist in a tight integration with 5G deployments below 6 GHz as well as 4G LTE. Fast adaptation to changing channel conditions will enable switching within and across cells to maintain performance and coverage. In addition, there will almost certainly be a key role for Software-defined networking (SDN) and network functions virtualization (NFV) in how networks operate and provide seamless connectivity for users. 

With these high-band mmWave frequencies, radio propagation is much weaker than at the low bands. Signals are easily blocked by buildings, foliage and even human bodies. This means that networks will need to be densified to maintain coverage and the user experience. Inter-site distances (ISDs) of less than 100m will be common, with indoor high density networks seeing ISDs as low as 10m. Such deployments are best achieved with 5G mmWave small cells.

Nokia has made two new additions to its AirScale small cells portfolio, which extends 5G both indoors and outdoors. There is a new compact millimeter wave (mmWave) radio for cost-effective 5G outdoor coverage. The radio is aimed at areas where there is extremely high traffic, such as airports, stadiums and busy pedestrian zones. The company also introduced a new 5G pico Remote Radio Head, for its Nokia AirScale Indoor Radio System. This device upgrades indoor coverage to 5G without replacing installed hardware, even in buildings such as hospitals and shopping malls. The 5G AirScale mmWave Radio supports 28 GHz and 39 GHz bands while the 5G pico Remote Radio Head supports sub-6 GHz.

- Challenges of 5G Implementation

Now with 5G, operators expect to implement high-bandwidth and low-latency technologies in applications to meet various use cases that business demands. With the rollout of 5G, operators face several challenges: 

• Spectrum bands are auctioned off, and wireless carriers need to bid for higher bands to build their proposed use cases, and that involves huge investments to buy the bands needed for 5G services.
• Multimode environments will apply millimeter wave (5G mmwave) wireless connectivity in urban areas where population density and data make short-range, high-bandwidth solutions optimal. Although 5G is a bit higher in frequency and can increase the speed of radio frequency (RF) waves above 28 GHz, it has its own advantages, because the higher frequency is more resistant to interference and is different from the range of spectrum currently deployed for previous generation networks. Compared to, it can carry 1000 times more data. It also has the disadvantage that it cannot travel that far, and it cannot almost pass through obstacles such as buildings. mmWave propagation results in higher path loss because higher frequencies have weaker non-line-of-sight paths and increase the effects of blocking (difference between 5g and mmWave).
• 5G small cell antennas are being used to fix and relay signals around obstacles and are distributed in a denser manner than current cell towers. These small arrays need to be more compact and accessible, for example mounted on top of street lights. Additionally, MIMO functionality requires different antennas to be synchronized on devices in the same frequency band.

[More to come ...]