Exploring Dual-Frequency Implementation for Semi-Passive RFID Tags

Radio Frequency Identification (RFID) tags face inherent limitations in power delivery and communication range. Ultrahigh Frequency (UHF) offers extensive reach but microwatt power transmission, while High Frequency (HF) boasts better power delivery but suffers from restricted range. EPC UHF air protocol is very suitable for semi-passive RFID used as a sensor node in Internet of things (IoT) applications thanks to its backscattering ability reducing power consumption and allowing to achieve a high transmission range. But the low power delivery inherent in UHF often requires another power source. EPC standards also provide a HF protocol which can be used for better power delivery. This paper will investigate the potential gains of a dual frequency implementation through both EPC HF and UHF protocols and includes an FPGA implementation to demonstrate performance.