Increasing performance of SDR-based collision-free RFID systems

Maximizing the identification speed of Radio Frequency Identification (RFID) tagged items is one of the main challenges in the area than can bring significant benefits to a vast array of applications. The dominating UHF EPC Gen2 protocol only specifies collision avoidance algorithms and, although collision recovery techniques have been investigated by researchers in the past, no attempt has been made to leverage the application of such techniques with minor modifications to the RFID protocol and, hence, realistically improve its performance. In this paper, we show that a significant reduction of 26% in the inventory time with collision recovery is feasible in real time relying, for the first time, on actual measurements taken with a software-defined RFID Reader and off-the-shelf programmable Tags. Among the numerous applications that can benefit from an increased reliable RFID reading rate, we are highlighting the advantages of deploying our working prototype testbed in moving conveyor belt systems. In brief, we achieve a 26% belt speed increase maintaining the exact same reading reliability and up to 84% of RFID Reader power consumption savings.