Miniaturised dual-band s-shaped RFID tag antenna mountable on metallic surface

摘要

The RFID (Radio Frequency Identification) tag, as a substitute for the existing bar cords, recognises, modifies and tracks information through microchips mountable on an antenna. Among them, the UHF (860??960 MHz) RFID band tag has commonly been used in circulation and logistics fields throughout the world because of its low production cost and its read long range. This RFID tag must be miniaturised in order to be mountable on any product, and to minimise the antenna??s performance degradation. If it is used worldwide as a common product, broadband or multiband is required. Specifically, when the antenna is mounted on conductive materials, its impedance characteristics change and bandwidth decreases. Therefore, a tag antenna is required with impedance characteristics which do not change even when it is attached to metallic materials.