5. NFC Overview

What is NFC

NFC (near field communication) is a data transmission technology. However, a major difference from Wi-Fi, Bluetooth, infrared, and other data transmission technologies is that the effective distance generally cannot exceed 4 cm.

Three NFC working modes 

Reader mode (Reader/writer Mode)

In essence, the card reader uses NFC devices (such as Android phones supporting NFC) to read information from tags, stickers, newspapers, postcards, business cards, and other media containing NFC chips, or write data to these media. Currently, NFC tags are common on the market, and NFC tags are cheap and easy to use.

Card emulation mode)

The simulated card mode uses NFC-enabled mobile phones or other electronic devices as debit cards, credit cards, bus cards, access cards, and other IC cards. The basic principle is to encapsulate the information (Payment credential) in the corresponding IC card into data packets and store them in NFC-supported mobile phones. An NFC frequency converter is also required (equivalent to the card reader used to brush traditional IC cards ). When the mobile phone is close to the NFC frequency generator, the mobile phone will receive the signal sent by the NFC frequency generator. After a series of complex verifications, the information of the IC card will be transmitted to the NFC frequency generator, finally, the IC card data will be transmitted to the computer connected to the NFC frequency generator, and the corresponding processing (such as electronic transfer, open the door, and other operations ). If everything goes well, you will have successfully completed a "Mobile Phone farming" operation.

P2P mode)

This mode is similar to Bluetooth and infrared. It can be used for data exchange between different NFC devices, but the valid distance between NFC point-to-point mode is shorter (cannot exceed 4 cm ), in addition, the transmission speed is much faster than infrared and Bluetooth technologies, and the transmission speed is much higher than that of infrared blocks. If both sides use android4.2, NFC will directly use Bluetooth for transmission. This technology is called Android beam. Therefore, the two devices that use Android beam to transmit data are no longer limited to 4 cm.

A typical application of point-to-point mode is two mobile phones or tablets that support NFC for point-to-point data transmission, such as downloading music, exchanging pictures, or synchronizing device address book. Therefore, through NFC, multiple devices such as digital cameras, PDAs, computers, and mobile phones can quickly connect and exchange information or services.

Differences between NFC, Bluetooth, and infrared  Future prospects of NFC TechnologyElectronic tag Recognition

Brush mobile phone

Point-to-Point payment identification information record