What is the difference between a barcode and an RFID tag? What are the types of RFID tags?

Bar codes and RFID tags are both item information identification technologies, and their essence is to give a special number to an item, through which you can get information about the item.

The bar code is numbered by knowing the change of the image by optical means.

The RFID tag can be considered as the electronic version of the barcode, and its working principle is the radio principle. The number information in the RFID tag chip is obtained through the process of electromagnetic wave carrier and modulation.

RFID tag category:
Low-frequency electronic tags:
Its operating frequency range is 30kHz ~ 300kHz.

Typical operating frequencies are: 125KHz, 133KHz (There are other frequencies close to it, such as TI uses 134.2KHz).

High and medium frequency electronic tags:

The working frequency of mid-to-high frequency electronic tags is generally 3MHz ~ 30MHz. Typical operating frequency is 13.56MHz.

UHF and microwave tags:
Ultra-high frequency electronic tag, its typical working frequency is: 433.92MHz, 862 (902) ~ 928MHz;
Microwave range: above 3GHz

Ultra-high frequency (UHF) ranges from 300MHz to 3GHz, and microwave ranges above 3GHz. RFID systems using UHF and microwave are called UHF RFID systems. Typical operating frequencies are 433MHz, 860 ~ 960MHz, 2.45GHz, 5.8GHz, and the frequency wavelength is around 30cm.

UHF tags can be active or passive, and communicate with the reader through electromagnetic coupling. The communication distance is generally greater than 1m, typically 4-6m, and the maximum can exceed 10m.

Radio waves in the UHF band cannot pass through many materials, especially suspended particulate matter such as water, dust, and fog.

UHF readers have very high data transfer rates and can read a large number of electronic tags in a short period of time.

The reader is generally equipped with a directional antenna, and only tags within the directional wave speed range of the reader antenna can be read and written.

The antenna inside the tag is long and label-like. The antenna has two designs, linear and circular polarization, to meet the needs of different applications.

The data storage capacity of UHF tags is generally limited to 2048bit.

From a technical and application perspective, tags are not suitable as a carrier of large amounts of data. Their main function is to identify items and complete the non-contact identification process. Typical data capacity indicators are 1024bit, 128bit, 64bit, etc.

Typical applications include supply chain management, production line automation, air parcel management, container management, railway parcel management, and logistics management systems.