A novel reader anti-collision protocol using Priority Cluster for dense reader RFID system

In multiple readers environment, the Reader Collision Problem (RCP) deteriorates the performance of RFID system. In this paper, we proposed a novel reader anti-collision MAC protocol called Priority Cluster Protocol (PCP) to solve RCP. According to PCP, clusters are constructed dynamically by readers so that every reader in cluster is given priority to identify tags in sequence without collision. Furthermore, two strategies are introduced in order to attain better performance. Firstly, reading sequence of readers in the cluster is optimized further to minimize delay. Secondly, readers outside the cluster are also given opportunity to interrogate tags randomly when channel is idle temporarily. Simulation results and analysis show that the PCP improves significantly reading efficiency compared to traditional protocol such as PULSE, especially in dense reader RFID system.