Sussed them out.
There are lots of claims made for GPS signal jammers.
These have not been shown to work to date, IIRC.
The point would be to jam the missiles reception of the broadcast GPS signal, which it needs in order to know its own location. The missiles themselves would have the target coordinates loaded prior to launch.
The missile guidance system takes the missile location vs the target location and constantly updates the avionics to get the thing from point A to point B.
If Russia has effective GPS jammers these would be short range devices usable as point defense for a specific target zone.