Flexible RFID tag for bottle labelling

• Main Author: Rodrigues, David da Costa Guilherme Cheis
• Publication Date: 2021
• Format: Master thesis
• Language: eng
• Source: Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)
• Download full: http://hdl.handle.net/10400.21/14193
• topic: Radio frequency identification; Antenna; Tag; RFID tags on bottles; Impedance matching; Antenna size reduction; Identificação por radiofrequência; Antena; Tags RFID em garrafas; Matching de impedânica; Redução de tamanho de antena

Radio frequency identification technology is increasingly being used as a solution for identification services and for retail product inventory control. However, it remains a major challenge to fully replace existing technologies with RFID due to the unavailability of antennas applicable on any type of product. An example of this difficulty is the use of these antennas on bottles. The presence of a liquid drastically changes the performance and adaptation of the antennas, making them non-functional for this type of products if they were not specifically designed for it. The subject of this dissertation consists in the development of a flexible RFID antenna that works when applied to a bottle with liquid. For this purpose, antenna size re duction techniques and impedance matching techniques between the antenna and the microchip are studied in order to substantially reduce the size of an already operational antenna and make it functional for a bottle filled with liquid. RFID tags were built to work in free space and then modified to be applied to bottles with liquid. The tags’ size was reduced to one third of their original size. The results obtained, from tests carried out to achieve the maximum reading distances of the an tennas, show that they perform well when applied to the environment for which they were designed. It is also perceptible in these tests that changes in the environment such as changing the liquid inside the bottle reflect changes in the performance of the antennas making them non-functional.