US carrier AT&T is using new frequencies in the 600 MHz range to noticeably boost its users' upload speeds. The company announced the move in early August 2026. AT&T didn't give specific data rates, but the step shows just how heavily AI applications are now taxing the return channel of mobile networks.
Why the upload becomes a bottleneck
In the US, the uplink has traditionally been underdeveloped. According to a recent analysis, carriers there dedicate an average of just 5.1 percent of their total network capacity to the upload, putting them last worldwide. That's exactly where AT&T is stepping in. CEO John Stankey said during the quarterly earnings presentation that several uplink innovations are on the way. The new 600 MHz spectrum should help build better upstream capacity to support growing AI traffic and applications driven by AI agents.
The reasoning: a strong position in the low band is seen as key to a robust return channel. AT&T considers itself well positioned here and wants to extend that advantage with the 600 MHz spectrum. The company gained access to the frequencies through the recently completed Echostar transaction worth over 23 billion US dollars, which includes around 30 MHz in the 3.45 GHz mid-band and 20 MHz in the 600 MHz low-band nationwide. The mid-band frequencies for more 5G capacity are already active, while the low-band requires new antennas since the network doesn't yet support 600 MHz.
New antenna technology from Ericsson
The matching 600 MHz dual-band antennas come from AT&T's main supplier Ericsson. The Open RAN technology supports both the 700 MHz band and the new 600 MHz. For the first time, it uses upload-enhancing 8RX technology with eight receive paths in the low band.
AT&T promises significant improvements as a result: a doubling of average speed, up to 80 percent fewer upload disruptions, around ten percent fewer dropped calls, and up to 70 percent less throttling and congestion. For users sending large amounts of data upstream, such as video calls or AI-assisted services, that would be a tangible gain.