[kragen]

This is not correct. Low-data-rate satellite communication is generally received on the satellite with omnidirectional antennas, because if you try to do it with directional dishes, any problem with your satellite's attitude control system or position estimation leaves you with a dead satellite, because the directional dish on the satellite is pointed somewhere you don't have a transmitting antenna. Attitude control problems can be serious in any case (for a publicly known example, see Kepler), but if you can't communicate with the satellite you have no chance to fix or work around the problem, or even find out what it was so the next satellite doesn't have it.

[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.

[kragen]

Oh, that makes sense! Thanks for explaining!