3GPP agreed at its meeting in Sorrento, Italy, this past week to start a work item dubbed NR-U, which will define how 5G New Radio is introduced in unlicensed spectrum.
The work item covers five scenarios with functionalities such as Carrier Aggregation (within one eNodeB), dual connectivity (across two eNodeBs), LTE anchor in licensed spectrum, 5G NR anchor in licensed spectrum, uplink only in licensed spectrum, downlink only in unlicensed spectrum as well as standalone operation, explains Lorenzo Casaccia, vice president of Technical Standards at Qualcomm Europe, in this blog.
It's the standalone operation that is particularly interesting.
“To me, it was exciting because it’s really the first time for 3GPP … to start the project to define a 3GPP technology” that uses unlicensed spectrum, he told FierceWirelessTech.
Operators still prefer licensed spectrum because it gives them more control over the quality of their services, but unlicensed is increasingly becoming a part of the operators’ spectrum toolbox. Operators report big speed boosts after introducing LAA, a 3GPP Release 13 technology that uses carrier aggregation in the downlink to combine LTE in unlicensed spectrum (5 GHz) with LTE in licensed spectrum.
Casaccia suggests that the ability to operate 5G NR standalone in unlicensed spectrum could lead to local private 5G networks dedicated for a specific application such as industrial IoT or mobile broadband for enterprises, or it could provide an avenue for service providers, like cable operators and ISPs or neutral host service providers in public venues such as sports stadiums and malls.
But it’s also about enabling new use cases that have yet to be envisioned.
“I don’t know all the opportunities” that are possible, he said. “I see it more as an enabler to bring cellular into future opportunities that I don’t know about.”
Of course, 5G in unlicensed spectrum will still need to coexist with Wi-Fi and the Wi-Fi community no doubt will be watching this development closely. But given that the same companies in 3GPP are also involved in efforts like the MulteFire Alliance, which spearheaded the introduction of LTE in unlicensed spectrum without requiring an anchor in licensed spectrum, a lot of the lessons learned should transfer to the 5G work.
The NR-U work item that was just approved by 3GPP supports both the existing 5 GHz unlicensed band as well as the new "greenfield" 6 GHz unlicensed band, according to Casaccia.
The FCC in October advanced moves to make up to 1200 megahertz of spectrum available for use by unlicensed devices in the 6 GHz band (5.925-7.125 GHz), and the agency just granted (PDF) Qualcomm the authority to perform 6 GHz building attenuation measurements in support of the pending FCC rulemaking.