A magnetic resonant loop antenna to enhance the operating distance of 13.56MHz RFID systems

A magnetic resonant loop antenna enhancing the operating distance by improving the wireless power transfer efficiency of 13.56MHz RFID system was proposed. The proposed resonant antenna consists of resonant coils arranged between source coil and device coil coupled to each of them. The effects of resonant coils were measured using a 13.56MHz RFID reader and tag system in addition to simulation using RF simulator. The measurement results from RFID reader and tag show that the maximum operating distance is increased by approximately 96% and amplitude of receiving voltage on the RFID tag antenna is increased by 18% thanks to the magnetic resonance loop antenna.