The status of T-Mobile US’ relationship with millimeter-wave (mmWave) spectrum is complicated. The high-band spectrum is part of its oft-repeated triple layer strategy for 5G, but the operator doesn’t market it as a game-changing technology anywhere close to the extent of its competitors Verizon and AT&T.

“Don’t get me wrong, millimeter-wave has its place, but [the idea that] this millimeter-wave thing is going to deliver a phone in your hand wherever you go with multi-gigabit speed, it’s mythical,” Neville Ray, president of technology at T-Mobile US, said at an investor conference this week.

T-Mobile is going to deploy mmWave as a capacity layer where it’s needed, he said, adding that “millimeter wave is where you finish rolling out a 5G network. It’s not where you start.”

The reason for that? “It’s propagation characteristics are incredibly limited, despite all the work we’ve done and the industry’s done in contrast to other spectrum sources,” Ray said. “We’ve deployed a bunch of millimeter wave across major cities. I still believe I have one of the largest millimeter-wave networks in the U.S. in Manhattan and New York, and we rolled that out some time ago.”

Indeed, when T-Mobile activated its 5G mmWave network in New York City in the early days of summer 2019, Moor Insights & Strategy senior analyst Anshel Sag called it “one of the best networks in the world” and described it as perhaps “the most broad 5G coverage of any city with 5G” at that time. 

T-Mobile is continuing to learn more about mmWave, but the most exciting use case for the technology is in-building and areas with high concentrations of people like stadiums and venues, Ray said. However, even in those environments it’s more for capacity than it is about 5G performance, he explained. 

“To sit there and promise multi-gigabit speed across a broad geography using millimeter wave, guys, it’s just mythical,” he said, criticizing Verizon’s marketing efforts around mmWave 5G. “I think expectations have been somewhat mismanaged. … We’ve got to be really clear with consumers what we’re delivering and how we’re delivering it because this noise and kerfuffle that’s out there isn’t helpful at this point in time.”

Ray was also eager to again share his thoughts on open radio access network (RAN) technology, which is gaining momentum but still faces a somewhat uncertain future.

“If you’re building greenfield, you know, it kind of makes sense to start building that way, but for us I’m not building those thousands of sites a month on an [open RAN] platform at this point in time,” he said, referring to T-Mobile’s ongoing $40 billion network upgrade.

“We’re supportive and we’re working better and harder to understand the [open RAN] story, but it’s not ready for primetime for us,” Ray said. “I never want to sound like the guy that’s not trying to drive innovation because we are and I think we’ve driven material innovation, especially around 5G,” he added, referring to T-Mobile’s work on frequency division duplex (FDD) for 5G in particular. 

While open RAN is an interesting opportunity, there are too many unanswered questions about intellectual property, research and development (R&D), and systems integration, according to Ray. 

“Today, I buy a solution from an Ericsson or a Nokia or a Samsung; it’s warrantied. I have one neck to choke. If something goes wrong I know where to go. In an [open RAN] environment you have to do a lot more heavy lifting as the operator,” Ray said.

His criticisms, while valid, aren’t shared by technology leaders at other operators, including some major brownfield carriers. AT&T CTO Andre Fuetsch recently told Bloomberg that the operator is using some Samsung equipment based on open RAN standards in a small part of its network, and Telefónica CTO and CIO Enrique Blanco recently committed to transition at least 50% of the markets served by the operator to open RAN by 2025.

Greenfield operators Rakuten Mobile and Dish Network are epitomizing the cause most aggressively with each relying exclusively on open RAN for their respective nationwide 5G networks. 

While T-Mobile supports open standards and interfaces, the commercial model behind open RAN, specifically claims that it can dramatically reduce capex and opex, are “a big [to be determined] to be perfectly frank,” Ray said. “Once folks get their head and arms around the integration costs of the various vendors, who carries all that cost, who protects all of that if you go forward and make sure that the R&D investment is happening, and in alignment across what can be a series of open RAN competing vendors, there are big challenges.”

Ray said he doesn’t want to knock open RAN too hard because the industry is working through those issues. “But there’s a lot of wood to chop there, and for us I know the fastest and quickest, the most meaningful way I can roll out a 5G network at real pace is what we’re doing today,” he said. 

“I’ve been doing this a long time and I’m not going to go and chase a bunch of capital efficiencies which I’m not sure exist at this point.”