A Versatile Flexible UHF RFID Tag for Glass Bottle Labelling in Self-Service Stores

Low-cost and versatile radio frequency identification (RFID) tag for bottle labeling is in great demand with the rise of self-service stores. Especially, robust performance is of great importance when the tag is needed to be attached on different liquid products. This paper proposed a versatile and flexible ultra-high frequency RFID tag for liquid products with glass bottles. The tag antenna is based on a simple loop structure, which has a strong concentrated magnetic field. As opposed to conventional dipole-based RFID tags, the loop-based antenna is less affected by liquid. Simulations and measurements of the tag have been carried out in different application scenarios. Significant factors, such as installation position, liquid amount and type, bottle shape, and thickness, have been investigated to find out their influences on the proposed tag. According to the simulation and experimental verification, the performance of the tag is robust despite changes of the significant factors, and specifically, the tag antenna keeps well matched around the FCC band and the reading ranges remain 1.6–2.5 m in multiply application scenarios. This makes the proposed tag versatile and feasible for a variety of liquid products with glass bottles in self-service stores.