How to improve the read rate of UHF RFID multi tag?

In the practical application of RFID, it is often required to read a large number of labels at the same time, such as the inventory of goods in the warehouse, the inventory of books in the library scene, and the reading of dozens or even hundreds of goods labels on the conveyor belt or tray. In the case of most goods reading, the reading rate is called according to the probability of successful reading.

Generally, UHF RFID is used when the distance to read is longer and the scanning range of radio wave is wider. Therefore, in the field of logistics and supply chain, UHF RFID technology is chosen all over the world.

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

Besides 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 the outer packaging, the way of placing the goods, the temperature and humidity of the environment, the height of the ceiling, and the influence between the reader and the reader, etc.

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

How to improve the reading rate of RFID multi tags?

In order to improve the multi tag reading rate, we must start from the reading principle.

When reading multiple tags, the reader queries first, and the tags respond to the reader’s queries successively. If there are multiple tags responding at the same time in the process of reading, the reader will query again, and the queried tags will be marked to make them “sleep”, so as to prevent them from being read again. In this way, there is a high-speed data exchange between the reader and the tag, which is called congestion control and anti-collision.

To improve the reading rate of multi tags, we can expand the reading range and extend the reading time, and increase the number of information exchange between tags and readers. In addition, the high-speed communication method between reader and tag can also improve the reading rate.

In reality, however, the situation is too complicated. For example, sometimes there are metal goods in the goods, which may cause some angles to be unable to read the label. Therefore, the direction of the antenna and the location of the goods are very important factors. We need a reasonable design to make the reader read the label at all angles.

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