RFID Reader Anti-collision Algorithm Using a Server and Mobile Readers Based on Conflict-Free Multiple Access

When many RFID readers are placed in a limited area, the RFID system may operate inefficiently due to reader-reader collisions. So reducing and resolving reader collisions is an important issue. Existing DCS and colorwave algorithms for RFID anti-collision may not exhibit desirable performance in the environments with the dynamically varying number of neighbor readers. In this paper, we propose a simple RFID reader anti-collision algorithm, conflict-free multiple access based anti-collision (CFMA). In our CFMA, by using the location information received from readers, the server quickly decides whether a reader is safe to operate without collisions with neighbors or not. The mechanism helps readers avoid reader collisions efficiently and simulation results show CFMA outperforms colorwave and DCS.