A Method to Improve Identification Performance of UHF RFID Systems

Abstract

Dynamic frame slotted ALOHA (DFSA) has been widely adopted to reduce tag collisions in Ultra High Frequency (UHF) radio frequency identification (RFID) system. In the existing DFSA algorithms, the reader needs to accurately estimate tag backlog and set a new frame length which is equal to the backlog to close to the theoretical maximum throughput 36.8% of the framed ALOHA. To overcome throughput limitation and improve the identification efficiency, we propose an efficient slot-hopped algorithm based on ALOHA protocol. The slot-hopped mechanism was used in each frame to skip collision and idle slots. Accordingly, the scheme significantly reduces collision and idle slots. The performance analysis and simulation results show that the proposed algorithm outperforms other ALOHA-based protocols .