T-Mobile US has been aggressive in extending the reach of its 4G LTE network using its sub-1 GHz spectrum holdings, but the carrier is keeping the depth of that support rather shallow as it prepares to support its 5G roll out.
Speaking to analysts during its most recent quarterly results conference call, T-Mobile US CTO Neville Ray explained that the carrier was using just 10 megahertz of its 600 MHz and 700 MHz spectrum resources to support its 4G LTE network. The carrier has varying amounts of that low-band spectrum across the country due to the specific licensing arrangements.
“We have a national average of 30 megahertz, so in some markets we have 40 and in a few places we have 50 megahertz of 600 MHz and less in some than the 30,” Ray explained, according to a transcript of the call. “We’re retaining the balance of that spectrum for the 5G roll out.”
T-Mobile US CEO John Legere added that it was not yet possible to dynamically allocate spectrum resources across 4G LTE and 5G, noting that capability was “not ready for prime time by any means.”
That limitation requires operators that are beginning to launch 5G services to set aside only “clean” swaths of spectrum for those services. This is why most of the current launches by Verizon and AT&T have used millimeter wave (mmWave) spectrum bands that are not being used for 4G LTE services.
Verizon has been quiet on its plans to layer in lower-band spectrum support for its 5G service. AT&T, on the other hand, recently said it would have nationwide mobile 5G coverage by early next year that relied heavily on the carrier’s lower-band spectrum holdings.
Legere did note that the carrier had deployed its standards-based 5G equipment in six of the country’ 10 largest markets, including New York and Los Angeles. The carrier has said it plans to have a nationwide 5G network in 2020.