How to improve the multi-tag reading rate of UHF RFID reader?

In the practical application of RFID equipment, it is often required to read a large number of tags at the same time, such as the inventory of the number of warehouse goods, the inventory of the number of books in the library scene, including the count of  hundreds of goods on conveyor belts or pallets. In the case of reading a large number of goods, it is called the reading rate according to the probability of being successfully read.

In the case where the reading distance is desired to be longer and the scanning range of the radio wave is wider, UHF RFID reader device is generally used. So what are the factors that affect the reading rate of UHF RFID?

In addition to the reading distance and scan 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 tag and the reader, the material of the outer packaging, the placement of the goods, the temperature and humidity of the environment, and the distance between the reader and tags etc. In the actual application of RFID, it is actually easy to be affected by the external environment, and these different environmental factors are intertwined with each other, which together constitute the key difficulties that need to be overcome in the implementation of RFID projects.

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

The reading principle of multi-tag : When multiple tags are read, the RFID reader queries first, 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, the high-speed data exchange process between the reader and the tag is called congestion control and anti-collision.

In order to improve the reading rate of multiple tags, we can extend the the reading range and reading time of the devices, and increase the number of information exchanges between tags and readers. In addition, the high-speed communication method between the reader and the tag can also improve the reading rate.

In addition, it should be noted in practical applications that sometimes there are metal commodities in the goods, which may interfere with the reading of non-metallic tags; the RF power of the tag and reader antenna will influence the reading distance; as well as the direction of the antenna and the placement of the goods are also very important factors, which require a reasonable design, and it is necessary to ensure that the electronic label is non-damaged and readable.


Handheld-Wireless is mainly engaged in the development and production of various types of handheld devices, providing hardware devices include android mobile computer and RFID handheld devices, as well as software customization services, supporting multi-tag reading, and providing inventory management and asset management solution etc.

Post time: Sep-17-2022