Design and Implementation of Long-Range RFID Reader for Sensor Tag System

ISO/IEC 24753 defines new modem specifications for long-range RFID communications and application protocol for sensor tag system. According to the ISO/IEC 24753, the frequency offset of the tag is 4%. In this paper, we designed a non-coherent receiver structure to solve the frequency offset problem. A frequency estimation block was designed to mitigate the effects of 4% frequency offset and a start frame delimiter (SFD) detection algorithm was proposed to determine the start position of the payload. We implemented a long-range RFID reader with the proposed methods and evaluated its performance in a wired network. The implemented long-range RFID reader showed more superior performance than the commercial RFID reader.