How to choose UHF RFID tag in the project?
UHF RFID tag has a wide market application scenario. It has the advantages of reading multiple tags at one time, long identification distance, fast data transmission speed, high reliability and service life, and withstanding outdoor harsh environment. It can be used for asset management, production line management, supply chain management, warehousing, anti-counterfeiting and traceability of various items (such as tobacco, alcohol, medicine, etc.), retail, vehicle management, etc.
At present, the common UHF RFID Air interface protocols in China include international standards, national standards, industry standards, enterprise standards, etc. The most popular standards are 6C and 6D standards, namely ISO / IEC 18000-6c (63) and ISO / IEC 18000-6d (64), as well as China’s national standard GB / T 29768-2013 officially implemented in May 2014.
The global definition of UHF electronic tag frequency band covers different areas, such as 840 ~ 844mhz and 920 ~ 924mhz in China, 865mhz ~ 868mhz in EU, 952mhz ~ 954mhz in Japan, 920mhz ~ 925mhz in Hong Kong, Thailand and Singapore, and 902mhz ~ 928mhz in the United States, Canada, Puerto Rico, Mexico and South America.
1. Environmental problems of label application
Especially for UHF RFID products, metals and liquids have a great impact on their performance. Therefore, the primary consideration is whether the application environment is metal or non-metal, liquid or plastic, glass, wood, etc.
Direct impact of raw materials on RF signal: metal has an impact on the RF signal of RFID tag. When used in metal articles or working environment with many metal effects, it is necessary to use anti metal electronic tag, so as to reduce the impact of metal on tag data signal and facilitate the normal use of RFID electronic tag.
The performance of UHF RFID tag is easily affected by the environment. If it is necessary to determine whether the product is suitable for the actual application environment, it must be directly used on the object in the early test stage to have reference value.
2. Factors affecting label recognition distance
The reading distance is also directly related to the reader and antenna. It is necessary to clarify the installation position and angle relationship between the label and the reader antenna. At the same time, the parameters of power selection, antenna gain, polarization mode and radiation angle all need to be considered.
In the whole RFID system, every detail may affect the actual reading distance and whether it can finally meet the project requirements. Even the length of feeder (cable connecting antenna and reader) needs to be considered in place.
3. Understanding of label size
In our past many project experiences, customers often want the label size to be very small, which is both beautiful and easy to install.
However, the size of the label is one of the main factors that determine the performance of the label. Generally speaking, the larger the size, the better the label performance can be designed. If the manufacturers are different, the models and specifications are different, the integrated IC production process and antenna manufacturing technology are different, and the price is different. Consumers should choose according to the actual use and cost budget.
4. Other considerations
In addition, there are other detailed considerations, such as whether the label has environmental reliability requirements such as temperature and humidity resistance? How much data capacity does the label need to write? What is the maximum number of tags to read at a time? etc.
