In practical applications of RFID, it is usually necessary to read a large number of labels at the same time, such as the inventory of warehouse goods, the inventory of books in library scenarios, and the reading of dozens or even hundreds of goods labels on conveyor belts or pallets. For reads of most shipments, the probability of a successful read is called the read rate.
In the place where you want to read farther, the scanning range of the radio wave is wider, and UHF RFID is generally used. Therefore, in the field of logistics and supply chain, UHF is the RFID technology of choice worldwide. Therefore, the author will further elaborate the reading rate problem for UHF RFID.
What are the factors that affect the reading rate of UHF RFID?
The read rate is not only related to the above-mentioned read distance and scan direction, but 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 labelers, the material to paste the goods and the outer packaging, the way the goods are placed, the temperature and humidity of the environment, the height of the ceiling, the influence between readers and readers, etc. .
I believe that after reading the above description, you will realize that in the actual application of RFID, it is easy to be affected by the external environment. These different environmental factors are intertwined, which together constitute the key difficulties that need to be overcome in the implementation of RFID projects.
How to improve RFID read rate and multi-tag?
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 reply to the reader's query successively. If you reply to multiple tags at the same time during the reading process, the reader will query again, and the queried tags will be marked and ordered to "sleep" to prevent further reading. In this way, the high-speed data exchange between the reader and the tag is processed, and this process is called congestion control and anti-collision.
In order to improve the reading rate of multiple tags, the reading range can be extended, the reading time can be extended, and the number of information exchanges between tags and readers can be increased. In addition, high-speed communication methods between readers and tags can also improve read rates.
However, in real scenarios, the situation is too complicated. For example, sometimes shipments contain metal cargo, which can cause tags to be unreadable at certain angles. Therefore, the orientation of the antenna and the placement of the cargo are very important factors. Reasonable design is required to enable readers and writers to read labels from all angles.
Moreover, even if all kinds of work are done well, other unexpected situations may occur, such as the electronic tag itself may be broken.
