RFID Working Principle
The basic working principle of RFID technology is not complicated: After the tag enters the magnetic field, it receives the RF signal from the reader and sends the product information (passive tag or passive tag) stored in the chip by the energy obtained from the induced current or The tag actively sends a signal of a certain frequency (Active Tag, Active Tag or Active Tag). After the reader reads the information and decodes it, it sends it to the Central Information System for data processing.
A complete RFID system consists of a reader and an electronic tag, a so-called transponder and an application software system. The working principle is that Reader transmits a radio frequency energy of a specific frequency to drive a circuit Internal data sent, then Reader will receive the interpretation of data in order to give the application to do the appropriate treatment.
To RFID card reader and electronic tags between the communication and energy sensing approach can be roughly divided into: inductive coupling and backscatter coupling two. Most low-frequency RFID mostly use the first type, while most of the higher frequency using the second way.
Depending on the structure and technology used, the reader can be a read or write / read device and is an RFID system information control and processing center. The reader usually consists of a coupling module, a transceiver module, a control module and an interface unit. The information exchange between reader and transponder is usually half-duplex communication, meanwhile reader provides energy and timing to passive transponder through coupling. In practice, management functions such as acquisition, processing and remote transmission of object identification information can be further implemented through Ethernet or WLAN. The transponder is the information carrier of the RFID system. The transponder is mainly composed of the coupling original (coil, microstrip antenna, etc.) and the microchip to form the passive unit.