RFID is the process by which items are uniquely identified using radio waves, and NFC is a specialized subset within the family of RFID technology. At a minimum, an RFID system comprises a tag, a reader, and an antenna. The reader sends an interrogating signal to the tag via the antenna, and the tag responds with its unique information. RFID tags are either Active or Passive.
Passive RFID tags primarily operate at three frequency ranges:
Low Frequency (LF) 125 -134 kHz
High Frequency (HF)13.56 MHz
Ultra High Frequency (UHF) 856 MHz to 960 MHz
NFC is a specialized subset within the family of RFID technology. Specifically, NFC is a branch of High-Frequency (HF) RFID, and both operate at the 13.56 MHz frequency. NFC is designed to be a secure form of data exchange, and an NFC device is capable of being both an NFC reader and an NFC tag. This unique feature allows NFC devices to communicate peer-to-peer.
Near-field communication devices operate at the same frequency (13.56 MHz) as HF RFID readers and tags. The standards and protocols of the NFC format is based on RFID standards outlined in ISO/IEC 14443, FeliCa, and the basis for parts of ISO/IEC 18092. These standards deal with the use of RFID in proximity cards.
As a finely honed version of HF RFID, near-field communication devices have taken advantage of the short read range limitations of its radio frequency. Because NFC devices must be in close proximity to each other, usually no more than a few centimeters, it has become a popular choice for secure communication between consumer devices such as smartphones.
Peer-to-peer communication is a feature that sets NFC apart from typical RFID devices. An NFC device is able to act both as a reader and as a tag. This unique ability has made NFC a popular choice for contactless payment, a key driver in the decision by influential players in the mobile industry to include NFC in newer smartphones. Also, NFC smartphones pass along information from one smartphone to the other by tapping the two devices together, which turns sharing data such as contact info or photographs into a simple task. Recently, you may have seen advertising campaigns that used smart posters to pass information along to the consumers.
Also, NFC devices can read passive NFC tags, and some NFC devices are able to read passive HF RFID tags that are compliant with ISO 15693. The data on these tags can contain commands for the device such as opening a specific mobile application. You may start seeing HF RFID tags and NFC tags more frequently in advertisements, posters, and signs as it’s an efficient method to pass along information to consumers.
At the end of the day, NFC builds upon the standards of HF RFID and turns the limitations of its operating frequency into a unique feature of near-field communication.