Keyword: HF, UHF

Posted on 16 Sep, 2019

The high-frequency RFID tag typically operates at 13.56 MHz, which is generally passive. When tagging and data exchange, the tag must be located in the near-field region radiated by the RFID reader antenna. The reading distance of the high frequency tag is generally less than 1 meter. Because the high-frequency tag can be easily formed into a card shape, it is widely used in electronic tickets, electronic ID cards, electronic lock-up anti-theft (electronic remote control door lock controller), residential property management, building access control systems, and so on.

UHF tags operate between 860MHz and 960MHz and can be classified into active tags and passive tags. In operation, the radio frequency tag is located in the far field region of the radiation field of the UHF reader antenna, and the coupling between the RFID tag and the electromagnetic coupling mode. The UHF reader antenna radiation field provides RF energy to the passive tag and wakes up the passive tag. The reading distance of the corresponding RFID system is generally greater than 1 meter, typically 4 meters to 6 meters, and the maximum is more than 10 meters. The reader antennas are generally directional antennas, and only the radio frequency tags within the directional beam range of the reader antenna can be read/written. UHF tags are widely used in railway vehicle automatic identification and container identification due to their long reading distance and fast data transmission rate. They can also be used in road vehicle identification and automatic toll collection systems.

Features of high frequency electronic tags and UHF electronic tags:

1. High-frequency tags are cheaper than UHF tags, save energy, penetrate non-metallic objects, and work frequency is not subject to radio frequency control. It is most suitable for objects with high water content, such as fruits.

2. UHF has a wide range of effects and fast data transmission, but they are relatively energy-intensive, have weak penetrating power, and can not have too much interference in the work area. They are suitable for monitoring items transported from the harbor to the warehouse. Moreover, the price of the UHF system is relatively high, generally about 10 times that of the high frequency system.