Delivering truly next-generation network speeds has been a challenge for U.S. cellular carriers, as their low, mid, and high band wireless towers have thus far required seriously awkward speed and distance compromises. Today, T-Mobile said it has successfully tested the next piece of its 5G strategy: Carrier Aggregation (CA) technology that will dedicate 2.5GHz mid band spectrum to downloads and 600MHz low band spectrum to uploads, simultaneously improving T-Mobile’s 5G speeds and reach across the United States.
In prior cellular generations, downloads and uploads generally shared a single radio frequency, equivalent to wired phone calls that put talking and listening through the same cable. Using carrier aggregation, T-Mobile is enabling a single phone to have separate inbound and outbound radio connections, spanning two radio frequencies that have been synchronized to seamlessly provide service together. This will let T-Mobile’s mid band towers handle outbound traffic at their best speed while slower but longer-reaching 600MHz low band towers take care of uploads, which don’t typically need to be as fast as downloads.