T-Mobile US has completed mobile data field tests using LTE-Licence Assisted Access (LTE-LAA) technology on its commercial 4G network. The trial, which took place in Los Angeles, achieved download speeds of up to 741Mbps, using 80MHz of aggregated spectrum. Further, T-Mobile says that it is the first national wireless provider to make LTE-Unlicensed (LTE-U) technology available to its customers. LTE-U uses publicly available 5GHz airwaves to bolster existing LTE capacity, and is now live in select locations in Bellevue, WA; Brooklyn, NY; Dearborn, MI; Las Vegas, NV; Richardson, TX; and Simi Valley, CA, with more locations rolling out later this year. The cellco clarifies that LAA enables greater carrier aggregation (CA) than LTE-U, so mobile operators can combine larger amounts of unlicensed and licensed spectrum.
In a parallel US trial, AT&T Mobility has confirmed that it has teamed up with Ericsson to conduct its own live LTE-LAA field tests, reaching initial wireless speeds of more than 650Mbps in downtown San Francisco. Previously, the mobile giant tested LTE-LAA at the Mobile World Congress in Barcelona earlier this year, reaching download speeds of up to 1Gbps by using LTE-LAA in tandem with CA, 4×4 multiple-input, multiple-output (4×4 MIMO) and 256 QAM functionality.
As previously reported by TeleGeography’s CommsUpdate, in February this year the Federal Communications Commission (FCC) took steps to authorise LTE-U devices in the 5GHz band. LTE-U and LAA devices and equipment intelligently tap into and share underutilised unlicensed spectrum without affecting other users on the same band, including those using conventional Wi-Fi. TeleGeography notes that LTE-LAA was standardised by industry body the 3GPP (as part of Release 13), while the parameters of LTE-U have yet to be formally defined.