Conceivable . . .
There has been a report or two of an Air Force tech or some such putting a design in a scanner and pressing a button and a satellite creating the crop circle.
But there are far more reports and photos of light orbs of various sizes but basketball sized or smaller, usually--flitting quickly about creating the circles while observers watched.
And, there's a significant number of reports of UFO type craft being over the field while the circle was being created or shortly before or after.
Of course, all the above COULD still be military stuff.
But the best researcher in the field--Linda Moulton Howe doesn't think it's military. I think she'd believe that some might be, but not all.
Plasma technology, holograms, etc., there's a reason they call it "active denial technology".