Telecom operators are constantly being judged on their network performance, which is becoming even more important with the deployment of 5G services. But what insight can these metrics provide when viewing the strategy operators have used to deploy those networks?

According to Ian Fogg, VP of analysis at Opensignal, the deployment strategies and end results are tied directly to what spectrum operators have access to and how they are deploying the infrastructure needed to support those spectrum bands.

All wireless communication systems are reliant on spectrum to transport a signal. The amount of spectrum a carrier controls or has access to provides the basis for the amount of information that can be sent using that signal.

Diving in further, where that spectrum resides has had a bigger impact on how operators have rolled out their 5G services. Lower-band spectrum, which is now considered spectrum below 2 GHz, has better propagation characteristic than mid-band (2 GHz-6 GHz) and millimeter wave (mmWave) spectrum that is generally above 10 GHz. This means that fewer antennas are needed for lower-band spectrum to cover a particular area than for higher bands.

However, because of that greater propagation, lower-band spectrum is used by more services and thus there is less total of it available to support commercial cellular services.

“What we've seen in the U.S. and globally is where carriers have got large amounts of new spectrum, typically above 3 GHz, in the 3 GHz to 6 GHz range, or in some cases millimeter wave that they can they can deploy and use for 5G services, that's where we've seen the big uplift in 5G experience over older technologies like 4G,” Fogg said.

These larger spectrum holdings are also important when using 5G technology as it can support much wider spectrum channels – up to 100 megahertz – as opposed to 20-megahertz channels for 4G LTE.

“If you're below 2 GHz, you're typically on a 10- or 20-megahertz channel,” Fogg said. “5G can use up to 100 megahertz per channel. If you're on a frequency band that's in the C-Band or 2.5 GHz band, it's much easier to have wide channels, these really wide channels and you get the full benefit.”

5G Deployment Impact

As for how this has impacted current deployments, Fogg noted that Opensignal’s most recent “5G Experience Report” showed that T-Mobile US provided the broadest availability, reach, and download speeds compared to Verizon and AT&T.

This advantage is based on T-Mobile US’ extensive 2.5 GHz spectrum holdings that it received when it acquired Sprint, as well as the carrier’s exclusive use of its low-band 600 MHz spectrum holdings for its 5G services. The former is a large swatch of spectrum, often in excess of 100 megahertz in some markets, that allows the carrier to provide high 5G speeds, while the latter is typically around only 30 megahertz of spectrum that provides for decent speeds and very broad coverage.

T-Mobile US’ advantage could be short-lived. Verizon and AT&T are both aggressively rolling out mid-band spectrum in the 3.7 GHz-4 GHz band (C-Band) that they spent tens-of-billions-of-dollars on to bolster their 5G services.

Verizon ended the second quarter covering 135 million potential customers with its C-Band spectrum, with plans to cover 175 million people by the end of the year. The carrier has already spent $2.8 billion on C-Band capex, with plans for up to another $6 billion for the rest of the year.

AT&T has been more conservative with its C-Band plans, hitting around 70 million people covered at mid-year on its way to 200 million by the end of 2023.

T-Mobile US is not sitting idly by. The carrier said its low-band 5G network covers around 320 million people, while its mid-band network covered 235 million people at mid-year on its way to 260 million people covered by year-end. To support those expansion efforts, the carrier increased its full-year capex forecast by $250 million, with it now sitting at between $13.5 billion and $13.7 billion for the full year.