NFC Credit Card to Implant

Your other antenna option, is to follow the circumference of the ring, so when you present it, rather than “punching” the reader , you are tapping your middle knuckle (Proximal Interphalangeal Joint)

regarding the antenna, if you get a pre-wound one like i shared above, you would measure the outer diameter of the ring and get an antenna, as close to that diameter or slightly larger

make sense?