A Reader Anti-Collision Protocol Based on Density for Dense RFID Networks

Radio Frequency Identification (RFID) Systems are wireless identification technology that provide communication and identification of tagged objects through wireless communications. In some applications, a single reader is not enough to cover a specific identification area, so several readers are placed very close to each other for optimal connectivity and coverage. This environment is called Dense Reader Environments (DREs). Such networks are susceptible to reader collision problems that cause decreases the performance of network. The reader-to-reader collision is an important challenge in dense reader RFID networks that lead to the reading throughput barrier and degrade the system performance. In this paper we propose a reader anti-collision algorithm based on the density of each reader in order to improve the network's throughput in dense RFID systems. Density Based Anti-Collision Algorithm (DBA) develops based on GDRA protocol but in this new algorithm each reader choice a time slot based on its density. Simulation results demonstrate the DBA algorithm provide 5.46% more throughput than GDRA.