A BROADBAND MODIFIED T-SHAPED PLANAR DIPOLE ANTENNA FOR UHF RFID TAG APPLICATIONS

In this paper, we report a single layer modified T-shaped dipole antenna for UHF-RFID tag applications. The designed RFID tag antenna consists of a pair of T-shaped dipole strips loaded with four half discs patches and a tag chip placed in the center. The antenna’s size is 80×40×1.6 mm3. Performance of the proposed design was investigated with simulations and measurements. The main feature of this design is that the RFID tag antenna can operate effectively at 868 MHz and 915 MHz frequency bands which make it broadband. The maximum reading range measured in an anechoic chamber is 4.25 m and 5.27 m at 915 MHz and 867.5 MHz, respectively. Furthermore, the RFID tag antenna can work on metallic plates when inserting a foam spacer between them. The final result has a simple configuration, low profile and can be suitable for practical applications dealing with free-space and metallic objects.