Looking for any advice and guidance in my requirements:-
Using 13.56Mhz RFID I need to detect people moving in and out of an area. This needa to be without any active action by the user, i.e they don't have to offer up their tag to a reader antenna.
Initial thoughts are something similar to retailers detectors, but I understand that's expensive.
Is there a way of extending range so that a doorway could be constructed to read? With 1m width that could be antennas either side capable of 50cm range.
The only other idea I had was a 'step' of some sort and have the users attach key fob style tags to boot laces in order to read as they moved across that threshold. Their feet is the only thing I could think of that is at a predictable distance from a reader, and the same regardless of height.
Other thoughts were a break beam type system of IR emitter/receiver, or ultrasound, but I was thinking it may be difficult to detect if groups cross in quick succession. These also don't allow me to identify anyone (player and which team they are on)
Any other ideas and advice would be appreciated.