RFID is a very mature technology that has been around for many years. It stands for Radio Frequency Identification and is used for one way wireless communication: capturing data stored in a tag. NFC is based on RFID technology and is still maturing. There are a number of differences between NFC and RFID but first let’s clarify some things about RFID. There are a multitude of different frequency bands associated with RFID but the most common are as follows based on reading passive tags:
|LF, low frequency||120-150 KHz||Up to 10cm|
|HF, high frequency||13.56 MHz||up to 1m|
|UHF, ultra-high frequency||902~928MHz (USA standard)||1-12m|
|865~868MHz (European standard)|
NFC stands for Near Field Communication and is based on High-Frequency RFID. It therefore shares many characteristics but also has some key differences which are illustrated in the table below.
|Operating Frequency||13.56 MHz||13.56 MHz|
|Communication||One way||Two way|
|Standards||ISO 14443, 15693, 18000||ISO 14443|
|Scan Distance||Up to 1 m||Up to 10 cm|
|Scan Tags Simultaneously||Yes||No|
As you can see NFC supports fewer standards than HF RFID and is limited in its reading distance which is typically 5cm or less. Another critical but purposeful limitation is that is can only read 1 tag at a time. The key difference and major advantage of NFC however is the support for 2 way communication and this offers 2 modes, tag emulation and P2P (peer-to-peer).
Tag emulation means that an NFC device can emulate a tag as well as read it. The typical application for this is to use a smartphone in place of a contactless payment card.
P2P mode means that NFC devices can share information without the need for a network infrastructure. Typically the process would be to pair the devices (both devices perform a tag read and tag emulation) and then share information. For example connecting to a WiFi hotspot by tapping it, or pairing to a printer by tapping it and then being able to print, or pairing two similar devices to play a game or share information.