5G

T-Mobile deploys 4 carrier aggregation in live network

T-Mobile says it is rolling out four-carrier aggregation on its standalone (SA) 5G network. It will combine four different 5G channels (or carriers) to deliver greater speed and performance. 

The four 5G spectrum channels are: two channels of 2.5 GHz, one channel of 1900 MHz and one channel of 600 MHz. This creates an effective 225 MHz 5G channel with peak speeds of up to 3.3 Gbps.

“That’s like taking four separate highways and turning them into a massive superhighway where traffic can zoom faster than before,” stated T-Mobile in its announcement.

T-Mobile isn’t yet specifying what locations in its network are receiving the benefit of the four-carrier aggregation. The company says it will be available nationwide in the coming weeks.

The company is currently unable to deploy the 2.5 GHz spectrum that it paid $304 million for in last summer’s FCC auction. The FCC says it can’t license the spectrum to T-Mobile currently because Congress has allowed the FCC’s auction authority to lapse. Perhaps the delay with 2.5 GHz is hampering its ability to do four-carrier aggregation in some areas.

Initially, four-carrier aggregation will only work for T-Mobile customers who have the Samsung Galaxy S23. The company says more devices will follow.

T-Mobile first announced its four-carrier aggregation trial in March. In a keynote at Mobile World Congress in Barcelona, then President of Technology Neville Ray said that T-Mobile had achieved the world’s first four-carrier aggregation data call on its 5G SA network with a commercial device.

T-Mobile was the first U.S. carrier to deploy a nationwide 5G SA network. SA means that it uses 5G technology in both its radio access network as well as its cloud-native core network. And T-Mobile’s 5G SA is more fully deployed than the 5G SA networks of its competitors AT&T and Verizon.

But some have theorized that T-Mobile had to push harder to deploy its 5G SA because it needed 5G voice over new radio (VoNR) for its customers to make voice calls in rural areas where it didn’t have good 4G coverage. It deployed 5G on its 600 MHz spectrum to expand rural coverage. But then it needed VoNR so that voice calls would have decent quality.

Fierce Wireless reached out to T-Mobile to find out when iPhones will be able to handle four-carrier aggregation. T-Mobile did not immediately respond, but we’ll update this story if it does.