RFID working frequency guidelines and typical applications

• Author: fonkan
• Source: fonkan
• Date: 2018-09-05
• Views: 724Times

I. low frequency (from 125KHz to 134KHz)

 

 

 

In fact, RFID technology is first widely used and popularized in low frequency.The frequency is mainly operated through inductive coupling, that is, there is transformer coupling between the reader-reader coil and the RFID tag coil.The voltage induced in the antenna by the alternating field of the reader is rectified, which can be used as the supply voltage.The field area can be well defined, but the field strength falls too fast. 

 

Features:

 

1. The general working frequency of the card reader working at low frequency is from 120KHz to 134KHz, and the working frequency of TI is 134.2khz.The wavelength of this frequency band is about 2500m. 

 

2. In addition to metal material effect, generally low frequency can pass through the item of any material without reducing its reading distance. 

 

3. There are no special licensing restrictions for readers working at low frequencies around the world. 

 

4. Low-frequency products have different packaging forms.Good form of packaging is too expensive, but has more than 10 years of life. 

 

5. Although the magnetic field of this frequency decreases rapidly, it can produce relatively uniform reading and writing area. 

 

6. Compared with other frequency band RFID readers, the data transmission speed of this frequency band is relatively slow. 

 

7. The card reader is more expensive than other frequency bands. 

 

Main applications:

 

1. Animal husbandry animal management system

 

2. Application of car theft prevention and keyless door opening system

 

3. Application of marathon running system

 

4. Automatic parking fees and vehicle management system

 

5. Application of automatic refueling system

 

6. Application of hotel door lock system

 

7. Access control and security management system

 

International standards:

 

A) ISO 11784 application - coding structure of RFID animal husbandry

 

B) ISO 11785 application of RFID in animal husbandry - technical theory

 

C) ISO 142223-1 application of RFID animal husbandry - air interface

 

D) ISO 14223-2 application of RFID animal husbandry - protocol definition

 

E) ISO 18000-2 defines low frequency physical layers, anti-collision and communication protocols

 

F) DIN 30745 is the European standard defined for waste management applications

 

 

 

Ii. High frequency (working frequency is 13.56mhz)

 

 

 

The reader at this frequency no longer requires coils to be wound and can be made by etching the antenna.Card readers usually work through load modulation.In other words, the load resistance on the card reader can be turned on and off to change the voltage on the reader antenna, and the antenna voltage can be modulated by the remote card reader.If people control the connection and disconnection of load voltage through data, then the data can be transmitted from the card reader to the reader. 

 

Features:

 

1. The working frequency is 13.56mhz, and the wavelength of this frequency is about 22m. 

 

2. Except for metal materials, the wavelength of this frequency can pass through most materials, but it will often reduce the reading distance.The card reader antenna needs to be some distance away from the metal.