>>/51095/
A low tech solution would be to paint the bottom a specific colour.

An organised army(so neither of those involved in this conflict) could probably add some kind of protocol for it, like if an artillery battery wants to send a drone they look over a map to see what path it takes and then send a warning to any position it passes over that at such and such a time a drone will pass and be active in an area. Though that still isn't the best solution as often both sides will have drones in an area at the same time anyway.

But also, modern soldiers are increasingly getting battle management systems on tablets and such to get an understanding of where everything is. It would probably not be hard to link drones in with them, so you if you are wondering whose drone it is you just open up your tablet and look.