How to Improve the Read Rate of UHF RFID Multi-tags?

In the actual application of RFID, there are often situations where it is required to read a large number of tags at the same time, such as the inventory of the quantity of goods in the warehouse, the inventory of the number of books in the library scene, including dozens or even hundreds on conveyor belts or pallets. Reading of cargo labels. In the case of most goods being read, the probability of being successfully read is called the read rate.

In the hope that the reading distance is longer and the scanning range of the radio wave is wider, UHF RFID is generally used. Therefore, in the field of logistics and supply chain, UHF RFID technology is chosen worldwide. Therefore, the author will further elaborate on the issue of UHF RFID reading rate.

What are the factors that affect the UHF RFID read rate?

In addition to the reading distance and scanning direction mentioned above, the reading rate is also affected by many other factors. For example, the movement speed of the goods at the entrance and exit, the communication speed between the label and the reader, the material of the pasted goods and outer packaging, the way the goods are placed, the temperature and humidity of the environment, the height of the ceiling, and the reader and reader The influence between the devices and so on.

I believe that after reading the above description, you must realize that in the actual scene application of RFID, it is actually very easy to be affected by the external environment, and these different environmental factors are intertwined with each other, which together constitute the key difficulty that needs to be overcome in the implementation of RFID projects. .

How to improve the read rate of RFID multi-tags?

If you want to increase the reading rate of multiple tags, you have to start from the reading principle.

In multi-tag reading, the reader first queries, and the tags respond to the reader’s query successively. If multiple tags respond at the same time during the reading process, the reader will query again, and the queried tag will be marked to make it 'sleep' to prevent it from being read again. In this way, high-speed data exchange processing is carried out between the reader and the tag. This process is called congestion control and anti-collision.

If you want to increase the reading rate of multiple tags, you can expand the reading range and prolong the reading time, and you can also increase the number of information exchanges between the tag and the reader. In addition, the high-speed communication method between the reader and the tag can also increase the reading rate.

However, in reality, the situation is too complicated. For example, sometimes the goods contain metal products, which may cause the tags to be unreadable at some angles. Therefore, the direction of the antenna and the placement of the goods are very important factors, and a reasonable design is required to make the reader read the tag at all angles as much as possible.

Moreover, even if all kinds of work are done, other unexpected situations may occur, such as the electronic tag itself may be broken.