5G – it’s coming to a population center near you.

T-Mobile in a recent meeting with FCC officials said the first inklings of millimeter wave 5G technology will likely be felt in cities and larger population centers.

The Un-carrier told the FCC it expects initial use cases for millimeter wave 5G technology will include “small-cell applications in urban and suburban areas” to “fill-in coverage gaps” and “provide additional capacity where required.” T-Mobile said millimeter wave technology will also likely be used to “meet new application requirements, including for the Internet of Things.”

The comments came a part of a presentation T-Mobile gave to FCC officials last week in which it once again urged the FCC to support 5G deployments by combining the 37 GHz and 39 GHz bands.

Alongside Verizon and AT&T, T-Mobile has argued the two bands should be merged into single 3 GHz band with larger license block sizes. T-Mobile said the big chunks of “exclusively licensed, large bandwidth spectrum will be critical to the 5G ecosystem.”

The carriers have also encouraged the FCC to steer clear of its proposed “hybrid” regulations for licenses in the 37 GHz band. The proposed regulations would give licensees on the band the right only to deploy outdoor operations, while assigning indoor operating rights on the same channels and in the same territory to an as yet undetermined class of real estate owners or building tenants.

T-Mobile said outdoor-only licenses are “not economically viable” and will “reduce the value of the spectrum and limit service offerings.”

As Verizon explained in its filing, one of the main issues with the hybrid proposal for the 37 GHz band is that it may preclude operators from using the millimeter wave spectrum for indoor coverage.

“The NPRM assumes that operators will predominantly be interested in outdoor deployments, but that is not so,” Verizon wrote. “The (millimeter wave) spectrum will likely be used heavily in more populated, urban environments where indoor coverage is critical. As the Commission has pointed out, the vast majority of current wireless use is indoors. Operators may not be able to make a business case for developing the 37 GHz band without the opportunity for indoor deployments.”

It should be noted that T-Mobile – and the other carriers – do have some eggs in the millimeter wave spectrum basket.

The Un-carrier last month filed a request to conduct both indoor and outdoor experimental 5G testing in the 28 GHz, 38 GHz and 39 GHz bands near its headquarters in Bellevue, Washington.

Similarly, AT&T last month sought permission to test prototype and experimental 5G radio systems in the 28 GHz and 39 GHz bands at its laboratory office in Middletown, New Jersey. While Verizon has mainly focused its test efforts in the 28 GHz band, the carrier also stands to gain spectrum in the 39 GHz range from its recent deal with XO Communications.