Surfing mid-band waves for the perfect balance of speed and coverage

February 1, 2022

Forget K-pop…

The latest data shows that C-band and not BTS is the most popular band for 5G (countries that have auctioned these frequencies). Around forty countries have held C-band spectrum auctions over the last few years. In 2021 alone, US operators parted with US$80 billion to acquire C-band in the FCC auction. So, why are operators investing so much in C-band when it doesn’t deliver the blistering speed enabled by high-band frequencies?

In a previous blog, we covered 5G enabled by high-frequency bands (known as Millimeter-wave or mmWave) that deliver super-fast speeds over short distances providing Line-of-Sight (LOS) network coverage like Wi-Fi. These high bands can provide data transfer speeds about 600x faster than low-frequency bands used for 4G and initial 5G rollouts.

However, by looking specifically into the US market, you can see the reason why 5G needs to be more than just about blistering speeds. It’s also about coverage, with the most recent data showing that T-Mobile has the best nationwide coverage. Yet, they only provide 5G to just over 50% of the US population. So, although 5G enabled by high-band spectrum is like taking an existing highway and adding twenty new lanes to it, meaning that significantly more traffic can flow, all the C-band investments are so that operators can deploy roads where there are none today. For 5G to offer a better experience than 4G, it needs broader coverage and blistering speeds. Enter stage left, C-band.

The perfect balance

C-band and mid-band are often used interchangeably. The C-band designation by the Institute of Electrical and Electronics Engineers (IEEE) ranges from 4.0 to 8.0 (GHz); However, the U.S. Federal Communications Commission designated 3.7-4.2 GHz as C-band. The C-band frequency would now be a segment of the larger mid-band spectrum that ranges between 1 GHz and 6 GHz. Compared with the low-band spectrum used for 4G and initial 5G rollouts, the mid-band spectrum delivers faster throughput speeds and has far greater capacity. Mid-band also offers a much more extensive coverage area and can penetrate walls, which is something that high-band spectrum like mmWave can’t. It is arguably the most helpful and critical band for 5G because it brings together the best of both worlds: long-range for broad coverage, with high capacity and speed, and the ability to penetrate walls. In other words, the mid-band spectrum provides the perfect balance of speed and range.

Optimizing 5G enabled by C-band

For operators to deploy C-band, they can overlay it on top of existing cell sites without needing new cell sites (unlike mmWave), which provides access to a range of spectrum with fewer challenging propagation conditions than mmWave. Operators will need to add a new set of RU equipment, additional baseband capacity, and power and fiber. However, there are several challenges that operators need to overcome (The aviation industry has significant concerns that these new C-band airwaves could interfere with aircraft flight systems operating on the range of 4.2-4.4G).


Greenfield deployments

With RAN being the most expensive part of the network to deploy and manage, one of the challenges is that a lot of this RAN technology is greenfield, so this is not like 4G technology that has been tried and tested over many years. It is also being developed to support new features, large spectrum bandwidths, and multi-band carrier aggregation. While at the same time, many operators are also rolling out new cell sites using vRAN/O-RAN, which is another greenfield technology and increases the number of vendors supplying components in the RAN. Traditionally, operators have struggled to converge different vendor technologies into the same network.

The benefits of assurance across the entire network lifecycle:

So, operators need to deploy automated assurance solutions to test all this technology works together before it goes into the live network and then monitors cells to ensure performance, speed, and coverage as its often difficult to establish where bottlenecks that reduce performance are, and by using AI-driven assurance operators can pinpoint and resolve issues quickly. Once initial C-band sites are deployed, automated assurance will help operators identify the best spots to place other sites and plan neighboring cells (based on subscriber usage and demand).

Ensuring a consistent customer experience

The goal of the C-band spectrum is to provide customers with a significantly enhanced user experience with operators stating that it will deliver up to 1.4 gigabit per second, which is about 10x faster than 4G. Most operators are expected to offer this as an enhanced paid 5G package. So, the rollout of these services will need to be carefully monitored to improve RAN performance while ensuring customers are receiving the service they are paying for and to optimize cell locations so that coverage is consistent.

The benefits of automated assurance:

Operators need to ensure that customers don’t experience sudden drops in their service quality as handover takes place from 5G enabled by low to mid and then high-band spectrum. Automated assurance monitors handover and transitions from these cell sites and provides critical insights allowing the operators to optimize their RAN deployments.

Gaining a subscriber’s perspective into the RAN

Operators can spend up to 70% of their time discovering and investigating network degradations. However, not all network issues are equal because not all problems directly affect the customer experience. So, operators need to understand how many customers are affected by a specific problem and prioritize the resolution by the number of subscribers affected.

The benefits of probe-based assurance:

By deploying an automated assurance solution that is probe-based and monitors the end-to-end network from the RAN to core, operators can gain visibility into this greenfield technology from the user’s eyes and their real-life experience. Operators can then optimize and manage their RAN deployments and integrate them into their legacy network, ensuring subscribers receive an excellent 5G customer experience.
A probe-based solution provides operators with real-time subscriber analytics and advanced end-to-end troubleshooting capabilities by monitoring the control and user plane. This helps operators pinpoint customer-affecting network degradations and quickly perform root cause analysis to rectify issues. This subscriber-based coverage provides Key Performance Indicators (KPIs) and Key Quality Indicators (KQIs) for 5G enabled by low, mid, and high-band spectrum, allowing you to optimize your cell performance.

Conclusion: Automated Assurance is Critical

5G enabled by C-band can significantly boost mobile operators’ service offerings. However, deploying an automated assurance solution that includes RAN monitoring and covers the different bands will be essential to ensuring the performance of 5G RAN and delivering on its promise to customers. Monitoring and optimizing the RAN is part of our advanced assurance solution, RADCOM ACE. Our customers are already using the solution today to monitor, analyze, and detect degradations in 5G RAN performance in real-time. RADCOM ACE combines RAN and network core data to provide customer experience and end-to-end service performance visibility. With integrated AI/ML capabilities for RAN optimization, RADCOM ACE can automate this entire process and predict network issues while assuring a superior customer experience. Once these greenfield deployments are integrated into the network, RADCOM ACE will enable operators to optimize their RAN continually as more cells are added and different spectrum bands are running.

RADCOMize your Radio Access Network for 5G with RADCOM.

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The content is for informational purposes only, and you should not construe any such information or other material as investment advice.

The article is subject to RADCOM’s disclaimers regarding Forward-looking statements and general information under the links below:

RADCOM’s Forward-looking statements disclaimer

RADCOM’s General information disclaimer

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