AT&T has released a few details on its upcoming 5G network. We know a dozen cities will have 5G by the end of the year, and three of them will be Waco, Dallas, and Atlanta. It's even hinted that devices will come to market in time for consumers to try the new network as it launches. Which devices, though? And what about the future of AT&T's 5G? The company is being a little more forthcoming at MWC.
According to AT&T's Gordon Mansfield, the carrier is pushing ahead with millimeter wave 5G in the 39GHz band. This deployment is what's known as "non-standalone" or NSA. LTE will still provide the backbone of the network, but when you're in range of a millimeter wave 5G tower, a compatible 5G device can burst up to several gigabits per second with low latency. As for towers, AT&T says it's been planning ahead for this in its LTE network. As it moves toward a software-based network, some towers can be updated via software to operate on 5G.
The first consumer device with access to that network will be a WiFi hotspot or "puck." You'll have to wait until the middle of 2019 before AT&T can offer phones and tablets with 5G built-in (home broadband isn't on the agenda for now). These devices will also be on the NSA millimeter wave 5G network. That means none of these phones or tablets will operate at 5G speeds in most places. You'll need to be close to a 5G tower—somewhat closer than you have to be to a 4G tower. AT&T is using some new network technologies and beam-forming techniques to push millimeter wave as far as possible, but the frequency is too high for it to propagate easily through obstacles.
AT&T's millimeter wave 5G will use TDD (time division duplex) technology. That means it uses one frequency for upstream and downstream and they take turns. Most networks on 4G use FDD (frequency division duplex), which has dedicated up and down frequencies. Currently, TDD is only common in China. The first generation of 5G modems will only work on TDD, though. AT&T will wait for FDD 5G before it begins refarming spectrum at lower frequencies. There's no exact timeline here, but it's more than a year out. Still, 5G will happen late this year, at least for some of us.