NFC technology evolved from contactless radio frequency identification (RFID). The transmission range of RFID can reach several meters or even tens of meters, and only information reading and judgment can be realized. NFC technology emphasizes information interaction. Near field communication is operating at a frequency of 13.56 MHz running within a distance of 20 cm, and its transmission speed is 106 Kbit/s, 212 Kbit/s or 424 Kbit/s.
The Near Field Communication Forum defines three modes of operation (PDF):
P2P mode: Supports communication between two near field communication devices for information exchange and file sharing.
Reader/writer mode: Enables near-field energy-enabled devices to read relevant information from posters or exhibition information electronic tags.
Card emulation: Near-field communication devices, like smart cards, allow users to pay for retail shopping and transportation.
The NFC mobile phone has a built-in NFC chip that forms part of the RFID module and can be used as an RFID passive tag to pay for the cost. It can also be used as an RFID reader for data exchange and acquisition.
From the application mode, the NFC card analog, reader, and point-to-point modes are divided. The card emulation mode is usually called the read mode. The mobile phone terminal can be simulated as a normal contactless card to be read by the POS machine. This mode usually inherits the widely used applications, such as bank cards and access cards. Bus cards, etc., use NFC mobile phones as carriers and take advantage of mobile phones in terms of network, multimedia, and human-computer interaction. The application scenarios are similar to the existing ones; the reader-writer mode is often referred to as the main read mode, and the mobile terminal can read Take a non-contact card or a non-contact tag, this mode may inherit the existing application, such as the NFC phone as a POS machine to read the existing bank card, bus card, or NFC The newly defined application scenario, such as reading the NFC defined standard using an NFC mobile phone
The standard data in the sign-off realizes the functions of electronic business card, electronic poster, WIFI connection, etc. The peer-to-peer mode means that two mobile phone terminals directly transmit data by touching within a short distance, which is a new mode defined by NFC, and Bluetooth, WIFI has the characteristics of close proximity and simple configuration. In theory, any data interaction between two mobile phones can be realized by simple touch, such as synchronization schedule, location sharing, business card exchange and other functions.