T-Mobile has begun working with its chipset, radio infrastructure and device partners to start trialing LTE-Unlicensed (LTE-U) this year, the carrier's CTO said on Monday.

LTE-U refers to the use of LTE in 5GHz unlicensed spectrum bands. It's a technology first suggested by Qualcomm Inc. (Nasdaq: QCOM) and Ericsson AB (Nasdaq: ERIC) in late 2013, that will bring about faster speeds, lower latencies and potentially better coverage than with WiFi alone. It's been debated within the 3rd Generation Partnership Project (3GPP) over the past year, as it also has the potential to cause interference if LTE "takes over" the WiFi it's riding on. (See Why Some Operators Think LTE-U Is Rude and Jury Still Out on LTE-Unlicensed.)

T-Mobile US Inc. was an early supporter of the technology, and the carrier's CTO Neville Ray writes in a blog post Monday that it plans to trial LTE-Unlicensed -- which it calls "Licensed Assisted Access (LAA)" -- in 2015 and "bring the technology to our customers in the near future."

"Importantly, LAA brings all of LTE's efficiencies -- sophisticated Quality of Service controls and robustness -- to the unlicensed band in a way that compliments Wi-Fi yet provides far greater coverage performance," Ray writes. "As the technology matures, we plan to use it in our continuing efforts to evolve and improve our Data Strong network and provide our customers with superior mobile broadband performance."

For more on T-Mobile's network upgrades, peruse the dedicated mobile content channel here on Light Reading.

Ray says that there is currently 550MHz of under-utilized spectrum in the 5GHz Unlicensed National Information Infrastructure (UNII) band that's available for use within the Federal Communications Commission (FCC) 's rules for the band. It will be among the first US carriers to take advantage of it. Verizon Wireless is also interested in deploying LTE-U, but AT&T Inc. (NYSE: T) has expressed reservations.

NTT DoCoMo Inc. (NYSE: DCM) and Huawei Technologies Co. Ltd. were the first to demonstrate the technology works in multiple pre-commercial networks this summer. (See NTT DoCoMo, Huawei Prove LTE-U Works.)

T-Mobile's LTE-U trials, however, won't necessarily be smooth sailing as it needs to prove the technology doesn't cause interference, as well as figure out how to market and price LTE-U speeds. The carrier has recently made a big push around WiFi and there is concern that LTE-U could weaken that investment or at least call into question when LTE-U is necessary as an alternative to WiFi. (See T-Mobile Turns Up VoLTE-to-WiFi Handoff and The Many Faces of 5G .)

— Sarah Reedy, Senior Editor, Light Reading