The current 5G service is built on the existing 4G core and 4G signaling, the so-called Non-Standalone Mode (NSA). The signaling and data transmission are asymmetric in that they are run on different frequencies. The 5G data bearer uses in most cases the 3.5GHz frequency band while the 4G signaling channel uses lower frequencies.
In theory everything works well and the 5G subscribers always get a 5G service when they are in the planned coverage area. In most cases this probably is so, but there are many situations where the planned and effective 5G service differ. A customer who has a high-end 5G phone with an expensive 5G data plan will not be happy.
The network operations center has a huge amount of information on the performance of the network, from very low level details from the cell sites to high level KPIs. Yet, they do not see what the customer experiences, where and when.
Netradar can help in building the best possible 5G service in your network. We collect extensive performance and contextual data that can produce a wealth of different analytics to shed light on how the end users, your customers, really see your 5G service and how it works in their daily journey.
In the following, we show some examples how Netradar data can be used to build the best possible 5G service.
Signal coverage of 5G
Your network planning tools give one estimate of where the 5G bearer should be strong enough to carry data. Yet, as the most common frequency in 5G is 3.5GHz, it will propagate differently, e.g. it has a shorter effective range than earlier used frequencies and does not penetrate buildings as well.
In particular the indoor coverage may be very challenging to measure and locate the places that need better planning.
• Coverage of 4G signaling in 5G NSA
In a 5G NSA service, the 4G network offers the control signaling to the devices. The availability of 5G is advertised inside the 4G channel parameters. In an optimal case, the 5G is advertised in the same area the new radio is really available. Often the same base station offers the 4G signaling and the 5G bearer.
With the Netradar analytics, we can see where the 5G service is being advertised by the 4G signal.
• Difference between signaling and data bearer
As the frequencies are different and the propagation of the 4G and 5G signals are estimated based on models, we have situations where the network advertises a service that is not available in real life.
The Netradar analytics sees where 5G is being advertised by the 4G network and where people with 5G devices and subscriptions really do get onboard 5G. Digging further into the data, we can help understand why the customer does not get the new service and is instead left on 4G.
• Handovers between 4G and 5G
When both 4G and 5G are available, the network controls the service the customer gets. The decision on which radio service to choose is taken by the network. In most cases this works great. But with Netradar analytics, we can see situations where the customer’s device jumps back and forth between these two radio technologies. This increases delays in the data transmission and even full service loss before the new bearer is configured to carry the customer's data.
The new 5G service offers a higher peak bit rate and lower latency compared to 4G - at least in most cases. Yet, as the 5G service is run along 4G and the data bearer is running on a different frequency, there can be serious performance issues that affect the customer.
In general, 5G offers a lower latency. The industry talks about 1ms latency but this usually means the delay of the radio link, not an end-to-end delay to the content in the cloud. The 1ms delay could be possible if content is hosted in the base station itself, so-called edge computing.
In reality, we see a similar end-to-end latency with current 4G and 5G networks. 5G latencies tend to be a bit smaller but since the path to the content can be long, the benefits of a lower latency radio link diminish.
Yet, what we do see in our data, is that 5G users often have very high latency peaks in their data transfers. With 4G, the worst case latencies can be several hundred milliseconds in a congested network but with 5G we have seen latencies as high as 1.5 seconds in some networks. These indicate that something in those 5G networks is not working right.
Similar surprises we see also with 5G download speeds. The industry advocates 1 Gbit/s peak speeds, and sometimes consumers can get very high speeds. But we also see very low speeds in 5G, even lower than 4G offers in the same location. In these cases, the device was using a very bad 5G bearer even though a better 4G signal would have been available. We also see network congestion events in 5G that lead to download speeds of less than 10 Mbit/s - not a tremendous service for a premium subscription.
The above are only some examples of analytics and views we can offer to a 5G provider. In a future post, we will look in more detail in these cases with real data from mobile networks. Stay tuned!