Research On Tree RFID Anti-collision Algorithm Based On Parallel Recognition And Prefix Grouping

With the advent of the information age,the Internet of Things industry has developed vigorously,and has been widely used in logistics management,artificial intelligence,autonomous driving,smart home and other fields.An era of interconnection and interconnection of all things is coming.As the perception layer in the structure of the Internet of Things,RFID technology has attracted more and more attention from researchers at home and abroad.When multiple tags send processing data to the reader at the same time,the communication channel is blocked,the data received by the reader is damaged,and normal read and write operations cannot be performed.This is a tag collision.Reducing tag collisions and ensuring the integrity and correctness of data transmission is the key to improving the stability of the RFID system and breaking the technical barriers of the Internet of Things industry.The current RFID anti-collision algorithm mainly uses the time division multiple address(TDMA)anti-collision algorithm,which represents the non-deterministic algorithm based on ALOHA and the deterministic algorithm based on tree type.This paper mainly discusses the tree based anti-collision algorithm,analyzes several classic tree based anti-collision algorithms,and proposes two more scientific anti-collision algorithms: Parallel Identification Dynamic N-ARY Query Tree Algorithm Without Idle Time Slots(DIPQT),Improved Adaptive Multi-tree Anti-collision Algorithm Based on Prefix Group(PGAMT)?Aiming at the problem of unstable throughput and low recognition efficiency in the RFID anti-collision algorithm of Dynamic N-ARY Query Tree Algorithm Without Idle Time Slots,a Parallel Identification Dynamic N-ARY Query Tree Algorithm Without Idle Time Slots is proposed.The algorithm uses synchronous orthogonal code(Walsh)as the code division multiple access technology of spread spectrum code to realize the function of parallel identification of multiple tags in a single time slot,which also tracking the collision bits of the collision tags to predict the tag distribution and eliminating the non-existent Tag branch and use back query mode to reduce the number of data transmission and improve the recognition speed.For the problem that too many idle time slots and low system throughput in the process of tag identification on Adaptive Multi-tree Anti-collision Algorithm,a Improved Adaptive Multi-tree Anti-collision Algorithm Based on Prefix Group is proposed.The algorithm is divided into two stages: prefix grouping and tag identification.In the prefix grouping stage,the reader uses a query cycle to determine the query prefix of the tag in the range,and each prefix represents a group.In the tag recognition stage,an improved adaptive multi-tree anti-collision algorithm is adopted.By calculating the collision factor,the split fork tree is dynamically selected,and the collision tracking tree algorithm is used in the branch with a small number of tags.On the contrary,the dynamic quad fork Tree anti-collision algorithm is used that does not generate idle time slots.The theoretical analysis and simulation results prove that the two anti-collision algorithms have significant effects in reducing the total number of query slots,improving system throughput and query speed,and are more suitable for scenarios with a large number of tags.