Roaming Report – Part 6 – 5G Roaming in the US fixes the lack of no LTE-CA on some Devices!

When I was last in the US back in 2019, I noticed that quite a number of the test smartphones (from the EU) I had with me would not do LTE Carrier Aggregation (CA). Even worse, my devices where often sent to a 5 or 10 MHz Carrier, so data transfer speeds were abysmally slow in the single digit Mbps range. Already back then, I found such a device behavior pretty strange but hoped that time would fix this. Fast forward to 2024 and my recent visit to the US, where I could have another look:

While some of the test devices I had with me could do LTE CA very nicely this time, some of my high end test smartphones still refused to tell the network about their LTE Carrier Aggregation capabilities. Fortunately, the world has moved on, and the devices at least reported their 5G Non-Standalone capabilities to the network. This way, I could at least get one LTE carrier and one 5G carrier. And, as US operators have lit spectrum in the 3.5 GHz range (band 77) as well as in the 2.5 GHz range by now (the old Sprint LTE TDD spectrum), data rates were quite OK this time on the networks of all three carriers. This is because while I was still limited to 10 to 20 MHz on the LTE side, I got an additional 80 to 100 MHz of spectrum on the 5G side with ENDC (EUTRA – NR – Dual Connectivity) in most places I tried. So while the problem is not fixed, it is at least masked, and data rates with good signal conditions went well beyond 200 Mbps. In other words: Very usable, even on my ‘impaired’ devices.

So while European roamers might be fine for a while when roaming in the US, network use will keep rising and data rates will decrease again, unless a device is able to aggregate more carriers. Not only on the LTE side then, but also on the 5G side. Let’s hope the laggards catch up to those device manufacturers that do it right.