Optimization of Dual-L Antenna Designs for Portable RFID Reader

The development of small integrated antennas plays a significant role in the progress of the rapidly expanding commercial RFID applications. In this paper, a planar dual-L antenna is presented for a dual-frequency band application of portable RFID reader. The antenna can be used over dual frequency of 840 MHz-845 MHz and 920 MHz-925 MHz which is allocated for RFID use in China. Simulation and measurement were performed and the dual-frequency band with a return loss better than -lOdB were achieved. The overall bandwidth of the antenna is increased and the dual-L antenna can be applied to ultra high frequency of 860 MHz-960 MHz that is proposed for RFID use by ISO/IEC.