5G rollout challenges and considerations

We are entering a historical cycle of infrastructure investment in both wireline and wireless networks. This is due in part to the ever-expanding IoT ecosystem and the unleashing of billions of connected devices which will place new demands on 5G fronthaul networks as operators begin rolling out 5G. In order to scale to volume, significant capacity will need to be added to support this unprecedented network evolution and expansion. To enable this evolution, we are seeing the introduction of new spectrum bands and advanced technologies—innovations that will help operators profitably deliver the promise of 5G.

5G fronthaul networks: what you need to know

In 2020, C-band and CBRS auctions were front and center across North America. Fast forward and we’re now at the brink of massive 5G mid-band rollouts across those purchased spectrum bands. The need to seamlessly connect everything together—plus deliver more bandwidth—is resulting in a never-before-seen level of fiber infrastructure spending.

To increase network capacity, mobile network operators (MNOs) are prioritizing network densification in the mobile fronthaul and midhaul. With that comes the need to connect more macro cell sites, radios and small cells—all typically connected via the fronthaul and the midhaul—to centralized radio access network (RAN) hubs. These connections are increasing in speed, from 1G to 10G and 25G. Densification will also have a direct impact on the backhaul and the aggregation layers which are being upgraded to high-speed links of 100G and 400G.

In addition, operators are looking to support 5G advanced use cases with low latency and high reliability communication playing a critical role. Service level agreements (SLAs) will be much more stringent, creating the need for deterministic performance for bandwidth, latency, jitter, frame loss ratio and support for synchronization. The fronthaul network will undergo an evolution and introduce new technologies such as eCPRI, PTP and others. The RF environment is also becoming more complex with the introduction of multiple new technologies like massive MIMO (mMIMO), beamforming and active antennas. In short, 5G network rollouts will include many new technologies requiring increased speeds. For more details concerning the new technologies and challenges surrounding rolling out 5G, watch our Light Reading interview ‘Deploying 5G: considerations for future networks’.

The right 5G network test tools and processes: key for validating 5G deployments

Now more than ever, MNOs will need to ensure network quality, reliability and availability when deploying new 5G services. They need to simultaneously rollout multiple new technologies which will require a trained and qualified workforce. Plus, this all needs to happen relatively quickly, making it a challenge simply to keep pace. Finally, operators need to accomplish these goals while minimizing operational costs. To achieve this, it is essential that MNOs have the right 5G network test tools, as well as methods and procedures that are simple, automated and cover all key technologies.

Let’s look at a concrete example. During installation, a challenge for MNOs and contractors is how to make sure radio units are working properly and all beams are being transmitted correctly. Tools like an RF spectrum analyzer can demodulate the 5G NR signal, confirm proper transmission and see whether beams are being transmitted. Furthermore, with a non-standalone (NSA) architecture—as 5G depends on the 4G backbone—poor 4G performance will translate into poor 5G experience. Therefore, it is important to make sure that cell sites are not affected by RF interference or PIM issues. RF over CPRI test applications like EXFO’s iORF solution and real-time RF spectrum analyzers such as the 5GPro Spectrum Analyzer are tools that are required to ensure good performance of 5G networks.    

Another key factor to consider are the emerging network synchronization technologies for 5G—such as 1588 PTP—that operators are deploying around the world. When well-engineered and all elements are configured correctly from day one, networks are synchronized without any issues. But that is easier said than done as packet-based synchronization is new to many operators. In addition, 5G brings much more stringent timing accuracy requirements—in some cases in the nanoseconds to support TDD, advanced carrier aggregation and CoMP (Coordinated Multi-Point). Furthermore, identifying the source of timing issues is not a simple task. Between a defective piece of equipment, configuration issues, excess packet delay variation or network asymmetry, it can become quite challenging. And if not resolved, timing issues can easily degrade RF performance and impact QoS.

Rolling out 5G networks: lessons learned

Having the proper 5G network test processes and tools adapted for new, emerging technologies will be important for MNO operation teams and their contractors. They need procedures and test solutions that will help them accelerate their deployments. They need tools that are easy-to-use and easy-to-interpret—tools that eliminate time-consuming learning curves, can evolve with the technologies they’re deploying and support all their testing requirements.

Finally, due to the speed at which deployments are taking place, automated test applications and processes become essential. Operators need to track progress and obtain real-time visibility into the results of the work being performed by their technicians, contractors and sub-contractors. As a result, cloud integration of tools and procedures is now mandatory. To help them navigate through all this technological complexity and ultimately accelerate 5G network rollouts, operators are turning to their technology partners to provide viable solutions. Check out this short video as EXFO’s Sophie Legault, Director of Transport and Datacom Business Unit, and Terry Sweeney from @Light_Reading discuss the top considerations when rolling out 5G fronthaul networks.