My own choice for drones, at least for recon teams, are parachuted 40mm ones fired from a M203.
For gaming purposes, I like it for several reasons.
- I think it is possible in any timeline (with Morrow wonder tech).
- It gives the team a fixed number uses
- It does not provide over the horizon information I might not be ready to give.
- Uses existing launcher
- Does not take up much space
You can limit the reception to the AutoNav or add some type of portable receiver.