With the launch of the Samsung Galaxy S8—the first handset to support LTE-U—T-Mobile US has started the first network deployments of the technology that was at the center of so much controversy last year and one that is sure to be watched by Wi-Fi advocates going forward.

T-Mobile CTO Neville Ray was asked during the company’s first-quarter conference call on Monday about the status of LTE-U, and he noted that the Galaxy 8 is the first LTE-U-capable handset to hit the market.

“In a few locations now across the U.S., we’re starting to turn up LTE-U, there will be more of that as we move through ‘17, but we’re still doing a lot of outdoor testing, trialing,” he said. “Long story short, ’18, ’19, LTE-U and into LAA is a big deal in terms of capacity and capability for wireless networks going forward,” and the company is happy to be at the forefront driving the ecosystem from a radio and handset equipment perspective.

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RELATED: Samsung Galaxy S8 supports LTE-U, which both Verizon and T-Mobile aim to deploy

Ray was also asked to give his opinion of 2.5 GHz spectrum, which is what Sprint has a treasure trove of—and Sprint happens to be an oft-cited potential merger or acquisition target with T-Mobile. Ray steered clear of that talk specifically but said the biggest news around 2.5 GHz these days is High Performance User Equipment (HPUE), a phone-based technology.

Sprint has described HPUE as a breakthrough innovation with the ability to extend its 2.5 GHz coverage by up to 30%, including indoors. The LG G6 is the first device to be enabled with HPUE technology.

RELATED: Sprint unveils HPUE to optimize its 2.5 GHz network coverage

Ray said he’s seen discussions about how HPUE sort of levels the playing field between 2.5 and the more valuable, with greater propagation, spectrum in midband, and he doesn’t buy that 2.5 is the “new low-band” for 5G, which is going to be in all bands—low, mid and high.

"I’m sure they’re doing some work in optimizing. I think HPUE has some benefits for them but I think it’s going to be a far cry from leveling the playing field with midband spectrum,” he said.

That said, there is a lot of 2.5 GHz spectrum “inside that company,” and clearly it has usefulness for capacity. “I think HPUE helps. We haven’t seen the results yet that would make us hugely excited about comparable values with midband, but we’ll wait to see more,” he said.