[xyzzyz]

This is not the case with Starlink (and presumably Starlink) satellites. The ground stations use directional phased arrays. They can do it, because they keep good track of where each satellite is at any given moment, and do trajectory adjustments as needed.

[kragen]

Yes, groundstations are virtually always highly directional, except for, like, radio hams sometimes. (Even hams usually use yagis.) Possibly you didn't notice this, but I'm talking about the antennas on the satellites, which are the ones that could suffer interference (since they're the ones receiving the uplink frequencies we're discussing), not the groundstation antennas.

You always have to keep track of where each satellite is at any given moment.

What do you mean by "Starlink (and presumably Starlink)"?

[Jtsummers]

To add to this, we know what objects interfere with our satellite contacts. We keep their orbital positions (as best as possible) in mind when scheduling satellite operations to avoid communication failures (partial or total) caused by their interference.

This is often learned after the fact. A contact will fail or go badly and then you can examine what was around it at the time. Over a series of failures the offending satellite will be identified.

[xyzzyz]

Ah sorry, I misread you. I meant “presumably Starshield”, I think autocorrect replaced it with Starlink.