Implementation aspects of an SDR based EPC RFID reader testbed

A flexible UHF EPC RFID testbed based on an offthe- shelf software defined radio, i.e. the National Instruments USRP-2922, will be presented in this paper. The testbed will be used to develop a real-time localization system which uses an overlaid direct sequence-spread spectrum signal. Since the localization algorithm is intended to use low power spectral density broadband signals for ranging some hardware modifications and a fully custom FPGA implementation dedicated to the ranging purposes was necessary. This paper presents a system overview of the testbed and describes the hardware modifications in order to improve the overall system performance and be prepared for future MIMO radar applications.