Research And Application Of Tag Anti-collision Algorithm In RFID System

RFID(Radio Frequency Identification)uses radio frequency signals to conduct the two-way data communication with non-contact which to identify the target and get the related data sets.Because the technology has the advantages of no manual operation,non-contact automatic identification and the recognition speed.So it has a broad application prospects in each industry.The pros and cons of tag anti-collision algorithm in RFID determine the level of efficiency of the system identification.At the same time,it also has affected the RFID technology can be used in the real field.The main research contents and achievements of this paper are as follows:Firstly,the paper analyzes several typical anti-collision algorithms based on ALOHA algorithm and the binary algorithm.It also analyzes and compares the principle and performance of these two types of algorithms.Secondly,the existing tag anti-collision algorithm have some defects.For example,the recognition rate of ALOHA algorithm is not high.In addition,when the amounts of tags are increasing,for the binary collision algorithm,its interaction number is a lot,its communication data quantity is large,and its communication time is long and so on.The paper comes up with a new algorithm to improve those defects.The algorithm is a improved binary search algorithm based on hash groupIt is referred to as HGADBT algorithm.In the process of tags recognition,the algorithm in advance selects the division method to construct hash function for proper tag grouping.After received the group information,tags calculate their own ID information and then divide the frame length to get a remainder m.That is the group number assigned to the tags.Next we use an improved binary search algorithm to identify the number of tags within the group.In the process of recognition,the reader sends corresponding number and a request command of “1”.Afterwards,the relevant groups in line with conditional tags will response the reader's request.If a collision occurs,the reader will record the position of collision,and the “1” is placed in a low to high order.When the high collision position is placed with “1”,the “1” of low collision position is not changed.If the combination of bits in corresponding collision position less than the request parameters or equal to the request parameters,this tag will respond to reader's requests.Looping the above process until all tags are successfully identified.Through the experimental analysis,the new algorithm has a certain feasibility.Finally,it applies the innovative algorithm to smart home.Completing the accurate and rapid identification of goods in the environment of smart home.