The Research On Anti-collision Algorithm Of Radio Frequency Identification

The anti-collision of RFID system is very important, and it is also one of the key technologies of RFID systems.To solve the problem the RFID system tag collision, and to realize the fast identification tag, this paper based on the arithmetic of the Binary search trees type, improved a Binary Collision Bit Search algorithm (BCBS), this algorithm first detection tag transmit information, determine the position of the collision information, after a collision of information transmission only. Second, the back strategy, when the sequence detection after identification, came back, according to the opposite of a information search data to identify. Through to the BCBS algorithm and other commonly used the collision of algorithms of comparison. It reduces the repeat information transmission, and improves the transmission rate.At the same time, this paper based on the fixed type in the ALOHA algorithm is put forward, It improves dynamic framed slotted ALOHA algorithm. Firstly, the time frame of information transmission dynamic adjustment, with probability distribution calculated the number of retransmission, so as to get the best frame length. Secondly, according to the RFID system range electronic tag number of change, use method to estimate the probability to the number of identification tag, and it use appropriate frame length and complete information transmission of reader label. Simulation results show that the algorithm and the other ALOHA related algorithm has faster recognition and the characteristics of information accurately.In addition, under the premise of effective anti-collision. The premise of portable RFID reader use time is limited for low power. This paper designs the Multilevel Stepping Power and Dynamic Timeslot (MSPDT). The algorithm combines the improved dynamic ALOHA algorithm. It changes the power level of the reader according to the estimate of dynamic. The experimental results show that, with the tag number of change, reader power level dynamic adjustment, the response rate tags within the system has been effectively improved, and the energy consumption has reduced.