What is the relationship between RFID and NFC?

This is a seemingly simple, but very confusing problem. Even after working in this industry for many years, sometimes it may not be able to clearly express the connection and difference between the two. In order to clarify this problem, let's start with a simple illustration.

　　 It can be seen very clearly from the above picture that there is a big difference between the two, and there is an intersection at the same time.

The earliest prototype of RFID can be traced back to World War II. At that time, Allied radars added a radio transmitter to the radar in order to effectively identify the enemy and our aircraft. After the radar detects the aircraft, it sends a specific radio wave to the aircraft, if it is its own. The aircraft will reply to a radio wave. After the radar receives it, it can be determined as its own aircraft, and if there is no response, it is considered as an enemy aircraft. After decades of development, many frequency bands have been extended according to the differences in usage. The field of action also extends from the earliest single object recognition to scenarios such as near-field payment.

Compared with RFID, NFC started much later. Around 2003, the three IT giants of PHLIPS, SONY, and NOKIA gathered together to unify and add some unique things on the basis of the original RFID. The NFC technology was launched. .

　　 There are many ways to classify RFID, such as according to active or passive, according to energy transfer method, this article is only to clarify the relationship between RFID and NFC, so here we only discuss classification by frequency band.

　　According to different fields of action, RFID is divided into many frequency bands, from low to high:

　　1, low frequency: 125K, 134K

　　2, high frequency: 13.56M

　　3, UHF: 900M

　　4, microwave: 2.4G, 5.8G

Of course, these are not all frequencies, but just the ones that we have the most contact with every day. It should be noted that 900M and 13.56M, these two frequencies have the widest application range. Our commonly used bus recharge cards, meal cards, second-generation ID cards, and PBOC bank cards all belong to this frequency band, and are often used for inventory management. The majority is 900M.

　　Different from 13.56M, 900M is a general term, not an exact frequency. Each country is different. Our country’s frequency band is a little lower than 900M, so 900M is generally used as a pronoun.

The relationship between RFID and NFC:

　　 It can be seen from the above figure that the biggest common point is that they all use 13.56M, and 13.56M is the RFID frequency band that we have the most contact with. This is also the reason why many people will not understand the difference between RFID and NFC. In fact, the range of RFID is much wider than that of NFC. In addition to 13.56M, there are many other frequency bands, while NFC has only one frequency band of 13.56. The original intention of NFC is to exchange small data for near-field payment and loose authentication. NFC uses 13.56M as the basis and adds a point-to-point communication. Traditional RFID can only interact with a READER and a TAG at the same time, while NFC Data can be transferred between two READERs.

　　 At the same time, NFC is not compatible with all 13.56M RFID. It is only compatible with 14443 TYPEA and 15693 protocols with some trade-offs. It does not support 14443 TYPE B like our ID card.