NFC technology（Near Field Communications）evolved from contactless radio frequency identification (RFID), RFID transmission range can reach several meters, even tens of meters, can only achieve information reading and judgment, while NFC technology emphasizes information interaction. NFC operates at a frequency of 13.56MHz within a distance of 20 cm, and its transmission speed can be 106Kbit/ s, 212Kbit/ s or 424Kbit/ s.

The NFC Forum defines three modes of operation :

• Peer-to-peer mode (P2P mode)

Supports the communication between two NFC devices to realize information exchange and file sharing.

• Reader/writer mode

Enables the NFC device to read relevant information from posters or exhibition information electronic labels.

• Card emulation

NF-emulation devices do what smart cards do, allowing users to pay for retail shopping and transportation.

NFC technology originated from RFID, but compared with RFID, there are certain differences, mainly including the following contents:

1.Frequency of operation

NFC operates at 13.56MHz, while RFID operates at low frequency (125KHz), high frequency (13.56MHz) and UHF（860-960MHz）.

2. Working distance

In theory, the working distance of NFC is 0~20cm, but in the realization of the product, because of the use of special power suppression technology, the working distance is only 0~10cm, so as to better ensure the safety of the business. Because RFID has different frequencies, its working distance varies from a few centimeters to tens of meters.

3. Working mode

NFC supports both read and write mode and card mode. In RFID, the card reader and the contactless card are two independent entities that cannot be switched.

4. Point-to-point communication

NFC supports P2P mode, but RFID does not.

5. Application area

RFID is more used in production, logistics, tracking and asset management, while NFC works in access control, bus card, mobile phone payment，identification, gaming, e-ticketing, digital business card and social media connection and other fields.

6. Standard protocols

The bottom communication protocol of NFC is compatible with the bottom communication standard of high-frequency RFID, that is, it is compatible with ISO14443/ISO15693 standard. NFC technology also defines relatively complete upper-layer protocols, such as LLCP, NDEF and RTD. To sum up, although there are differences between NFC and RFID technology, NFC technology, especially the underlying communication technology, is fully compatible with high-frequency RFID technology. Therefore, in the application field of high-frequency RFID, NFC technology can also be used.

Summary

At present, nfc technology has been relatively mature and has been widely used in People's Daily life. Popular nfc products include nfc business card, nfc social media card, nfc woven wristband, nfc access control card, nfc payment card,nfc epoxy tag, nfc dog tag and so on.With Near Field Communications (NFC), feedback from smartphones could be instantaneous, richer and more detailed.