Taking the Mystery out of 5G Network Troubleshooting

2021-07-06  |  6 min read 

Troubleshooting wireless communications networks is a little bit like sorcery. It’s a mysterious process, often shrouded in secrecy. And as long as the process works — the root source of failure is identified and the issue is rectified — it doesn’t really matter how you got there.

Unlike most other aspects of wireless communications testing, there is no standardized methodology for troubleshooting, nor is there a set of tools that is commonly used across the board. There is no industry-wide set of best practices. Troubleshooting methods can vary by company, by engineering team, and even by project. Again, the mentality is: whatever it takes to find the root cause of the issue or issues and fix the problem is the right solution.

This of course can mean trying many different approaches to the problem. Making assumptions, testing those assumptions, trial and error, and a long process of elimination to get to the source of the problem. It can take days, weeks, and in some cases months to identify the source of an issue.

Troubleshooting can also lead to a lot of finger-pointing and frayed relationships. Whether it's in the lab or in the field, if the network isn’t working properly and the issue cannot be identified quickly, there is a natural tendency to search for where to focus the blame. Is it the UE? The base station? The test setup? And, like it or not, we are all for the most part inclined to assume that the issue comes not from the system we are responsible for, but from somewhere else.

But what if there was an easier way to do 5G network troubleshooting? A way that not only saved a huge amount of time, but could also accurately pinpoint the source of failures every single time. A way that could be trusted to be the source of truth, providing a definitive root cause, and eliminating the finger-pointing.

There actually is a way to do just that. WaveJudge, an over-the-air communications analyzer that recently came to Keysight in the acquisition of Sanjole Inc., is the first 5G over-the-air communications analyzer to provide visibility into the interaction between protocol and physical layers in wireless transmissions. And because it can monitor both ends of a wireless network from the middle of the network — rather than a particular endpoint — WaveJudge provides definitive analysis for troubleshooting and tracing the root cause of failures.

Most products that we think of in the wireless network are actually in some ways endpoints within the channel and have the responsibility of receiving traffic and sending based on what is received. For example, a base station is responsible for scheduling uplink traffic while sending traffic in the downlink. On the other end, the UE is responsible for sending traffic in the uplink while receiving data in the downlink. While these products may incorporate some logging capability, half of those logs account for what the product believes it is doing itself.

WaveJudge, on the other hand, captures and measures the traffic as it is, in the air, not as a point between the signaling layers and the physical layer (PHY), like many logs within the products at the endpoints of the network. Also, because WaveJudge is not participating in the conversation between the two ends of the network, it is able to depict what the conversation looks like from the air in the middle of the network. And, since it’s looking in both directions simultaneously, it can provide accurate insight and pinpoint the source of the root cause of any network issues.

Visibility into the interactions between the protocol and the physical layers is a huge advantage because of the ever-changing state of the physical channel and the resulting control channel, which accounts for all environmental factors such as interference and fading. By coupling PHY testing views with upper layer protocol analysis, WaveJudge is able to identify issues that most tools simply cannot see. This enables WaveJudge to serve as a “source of truth” in troubleshooting, doing away with faulty assumptions, process of elimination, and finger-pointing.

To learn more about WaveJudge, including how it can streamline and improve the process of 5G network troubleshooting, please visit the Keysight Sanjole Wireless Analyzer page, or listen to this episode of the All Things 5G podcast.

Learn more about Keysight's 5G Solutions and the WaveJudge product line: