A UWB Antenna for Chipless RFID Tag Detection

Recently chipless RFID systems have been developed to compete with the conventional identification systems. One of the crucial components in a chipless RFID system is the reader antenna which plays a key role to transmit the radio frequency wave to the tag and to receive the reflected wave from the tag. In such a system, it is desired to have a high gain antenna to improve the reading range. In addition, a low profile antenna is needed in order to implement in a compact size reader system. In this paper, a UWB high gain antenna for the detection of chipless RFID tags is proposed. An array of 4 by 4 antenna is designed, fabricated and measured. The operating frequency of this antenna is from 4.15 to 8 GHz. It yields 15.5 dBi gain at its center frequency. The array antenna was tested in a chipless RFID system with a promising performance in tag detection at a distance of 35 cm. Hence, the proposed antenna has the potential to be used for many applications.