UHF RFID and the passive RFID injected into people’s skin are quite different technology. The credit card sized antenna combined with a directed radio signal (and a license plate scanner for backup) can do several meters, but a tag in your body won’t be readable beyond a few centimeters. Unless you use an active radio, of course, but then you need to power that radio somehow.
As I stated previously, toll booth rfid work at 20+feet and 80+.
UHF RFID and the passive RFID injected into people’s skin are quite different technology. The credit card sized antenna combined with a directed radio signal (and a license plate scanner for backup) can do several meters, but a tag in your body won’t be readable beyond a few centimeters. Unless you use an active radio, of course, but then you need to power that radio somehow.