Radio frequency identification (RFID) technology, also known as radio frequency identification, is a communication technology that can identify a specific target without establishing mechanical or optical contact between the identification system and the specific target, and read and write related data through radio signals.

Radio frequency, generally microwave, 1- 100GHz, is suitable for short-distance identification communication.

RFID readers are also divided into mobile and fixed. At present, RFID technology is widely used, such as library, access control system, food safety traceability and so on.

The working principle of RFID is: after the tag enters the magnetic field, if it receives the special RF signal sent by the reader, it can send out the product information stored in the chip (passive tag, passive tag or passive tag) or actively send out a signal with a certain frequency (active tag, active tag or active tag) with the energy obtained by the induced current. The reader reads and decodes the information and sends it to the central information system for relevant data processing.