rfid inductor
Hi Logan,
I am not very expert in RFID. But I think it all depends to the frequency of operation. For example in 13.56MHz systems, the tag should be in the near field of the reader. So the principle of power transfer is based on inductive coupling. Thus it is better to say the coil tag is an inductor.
In the other hand, for very high frequency systems, for example at 2.5GHz, the tag will usually be in the far field of the reader, thus the principle of power transfer is based on radiation. So now you should consider the coil as an Antenna.
I hope that helps you.