Radio frequency identification(RFID) technology has the ability to automatically identify the target object.An adaptive searching prefix(AS) anti-collision algorithm for RFID based on encoding is proposed to reduce the identified time of the object tag.The reader makes full use of the collision information to adaptively generate a valid query prefix by asking the tags return the collision coded information.With no idle slots for tags to identify

AS reduces the number of queries and consumedly enhances the system efficiency.Besides

it has solved the problems of redundant data in the communication between the reader and the tags and other related issues.The effectiveness of the algorithm has been proved by the theoretical analysis in detail

and the error of the throughput between the values of the theory and the experiment does not exceed 5%.Simulation results show that AS not only achieves much better performance of the system

but also reduces the energy consumption of the tags.It improves the system efficiency by 72% and 20.1% respectively compared with Query Tree algorithm and Adaptive Multi-tree Search algorithm when the number of tags is over 1000

the throughput still maintains at about 61%.