I have a robot which should detect an approaching person and identify them in a range of about 1-3 meters. For that, the person should have something on their key ring, ideally without battery life concerns.
We have researched using passive UHF RFID that can reach that distance. The problem is the antenna and PCB are huge compared to our robot and could not fit inside.
We are now researching BLE (Bluetooth low energy).
Do you know if RPi 3 can works with BLE?
And what can be expected for the battery life of the beacon?