2) RFID - Each player has an RFID token that they carry with them, the turret tracks the tokens and fires at the coordinates of the RFID tag when it comes into the turrets range.
@srnet Just looked more into RFID tags, the tags themselves can give a distance reading back to the RFID reader with an accuracy of a few centimetres, maybe those might just work, only issue could be direction of target.
Active RFID readers can all report the distance of there tags using its Broadcast signal, it determines its range by the time it takes for the receiver to get a reply from the RFID tag. (according to a google search)
Hi @srnetThe information comes from this post https://stackoverflow.com/questions/14237110/calculate-distance-to-rfid-tag#19684963