OPRFID Technology

RFID technology is now very mature and has been applied to all aspects of social life, such as storage management, logistics and transportation, supply chain management, ticket management, clothing industry, retail industry, etc. to quickly occupy the market with the incomparable advantages of bar code technology, such as long identification distance, fast identification speed, not easy to damage, large memory capacity, etc. RFID technology can simplify the complicated process of traditional logistics transportation and improve the efficiency and transparency of goods circulation.

RFID electronic tag, commonly known as radio frequency identification, consists of RFID tags, RFID reader, data transmission and processing system. Electronic labels are divided into active and passive types according to whether they are equipped with batteries. Regardless of its power supply mode, the ultimate purpose of electronic labels is to identify goods, but the application scenarios of these two types of labels are different. Taking the traditional logistics system as an example, active tags are generally used in the storage field because of their strong signal and wide coverage, while passive tags are often used in the transportation process to strictly control the shipment volume and safety.

Active electronic tag is also known as active tag. Its working power is completely supplied by internal battery. At the same time, some battery energy supply is converted into RF energy required for the communication between electronic tag and reader. Different labels use different numbers and shapes of batteries.

Passive tag is also called passive tag. After receiving the microwave signal from the card reader (Reader), it can convert part of the microwave energy into DC for its own work. When the passive RFID tag is close to the RFID card reader (Reader), the antenna of the passive RFID tag converts the received electromagnetic wave energy into electrical energy, activates the chip in the RFID tag, and sends the data in the RFID chip.

Compared with passive tags, active tags are as follows:

Active label: the battery is installed inside. Due to the working environment of the battery, the battery cannot work normally under high or low temperature; The battery is generally disposable and cannot be replaced. The ideal service life index of the manufacturer is 7-10 years. Due to the different times of use and environment of each label every day, in the actual project, some labels can only be used for a few months, and some labels can be used for more than 5 years. The consistency of the system is poor and can not be controlled. However, with the development of technology, rechargeable active labels have been withdrawn, which has solved quite a major problem; Due to the internal installation of battery equipment, the label is large, thick and heavy, so the label can not be removed; It is impossible to achieve "one car, one card and one number", and it is easy to exchange cards; High cost; However, the active tag has a long operating distance, and the distance between the tag and the reader can reach tens of meters, or even hundreds of meters.

Passive tag: installed without battery, it works with wireless wave energy, so it can work normally in high or low temperature environment; The system consistency is very good. The service life of the passive electronic tag is more than 10 years, maintenance free; Because there is no battery drag, the passive tag has the characteristics of small size, light weight, thin and so on. It is easy to install and suitable for use in various fields; It can prevent the label from being removed; It can achieve "one car, one card and one number", and realize lifelong ID number marking and vehicle quantity information for vehicle quantity; Low cost; Compared with active tags, passive tags have a slight limitation in reading distance and adapting to the moving speed of objects. The reading and writing distance is usually within a few meters. Generally, RFID readers with high power are required.

With the development of RFID technology, semi passive electronic tags have been developed. The battery power supply in the semi passive electronic tag only supports the circuit in the tag that requires power supply to maintain data or the voltage required for the operation of the tag chip. The tag circuit itself consumes little power. Before the tag is put into the working state, it is always in a dormant state, which is equivalent to a passive tag. The internal battery energy consumption of the tag is very small, so the battery can last for several years, or even as long as 10 years. When the tag enters the reading area of the reader, it is stimulated by the RF signal sent by the reader. When entering the working state, the energy support for information exchange between the tag and the reader is mainly the RF energy supplied by the reader. The function of the internal battery of the tag is mainly to make up for the lack of RF field strength at the location of the tag. The energy of the internal battery of the tag is not converted into RF energy.