AFAIK it’s not so much a lack of collaboration. It’s more nuanced than that. The lower frequencies used by Europe for 5G are already allocated for amateur and

AFAIK it’s not so much a lack of collaboration. It’s more nuanced than that. The lower frequencies used by Europe for 5G are already allocated for amateur and other uses here in the US. I believe Europe has been more willing to take away amateur bands. However here in the US, the FCC was trying to maintain those existing allocations and thus they chose to reuse 3.7-3.98 GHz instead, which is currently allocated for fixed satellite and other links. Therefore what FCC did is potentially better for everyone, if we can find out that radio altimeters—which should be filtering out frequencies that never belonged to them—are still able to work correctly. The issue is that, as you may know, if you engineer for something but don’t actually regularly test for it, you never actually engineered for that case. Up until this point, this case was never tested in production… because it has never existed in production. At the end of the day, we are between a rock and a hard place.