Research On ALOHA Anti - Collision Algorithm Based On Dynamic Frame Time Slot

RFID, Radio frequency identiifcation, is a technology that can identify thetarget information without any mechanical or optical contacted betweenrecognition system and specific target. With the development of wirelesscommunication, portable equipment and intelligent sensor，RFID has been widelyapplied. However, as its non-contact type characteristic, there are some tagcollision and the security problems. Facing the widely application prospect，it’smore need to be able to design a suitable anti-collision algorithms and securityauthentication protocol. On one hand，in the environment with large number oftags, it can effectively realize the anti-collision of tags, so that the throughput rateof the system can achieve the optimization. One the other hand，it can guaranteethe security in wireless communications, to ensure the confidentiality of userprivacy.Aimed at these two points，the main work in this paper are as follows:1.The paper makes a research and summary of the current situation of RFIDtechnology, analyzes the important signiifcance of anti-collision performance andsecurity authentication in the RFID application ifeld. A detailed analytical andsimulation are made in the anti-collision algorithms and security protocol, andpoints out the deficiencies of these existing algorithm.2.In the motion environment of mass tags, this paper puts forward the groupconcept based on the collision problem. The theoretical reason is as below: In theALOHA algorithm, many tags are sending information by selecting any slot time,which means that the reader may be probabilistic in receiving information. Thenumber of tags for each frame received have a certain range. When beyond thisrange, it will largely affect the throughput of reader On the other hand，althoughthe binary search algorithm has high recognition rate, its long time extend mayaffect the efifciency of the system. In this paper, I design a new Anti-collisionalgorithm，which combines the frame slot of the ALOHA algorithm and thegrouping concept of binary tree. This algorithm has the character of bothprobability and determinacy. Finally, I guarantee that this algorithm has itsoptimization by MATLAB.3.In the aspect of security authentication properties of RFID, this papermakes a detail analyze of the complexity of security protocol. This paper addsCRC-8verification algorithm and two points search method in the backendmanagement information system, which can avoid the possibility that labelinformation are modified or misrepresented in wireless channel. It ensures the security of label information, and improves the operation efficiency of thesystem.This paper studies has a widely application field. According that people paymore attention to their privacy rights, and even in some high-end informationsecurity ifeld, it’s still a worth thinking problem that focus on the security ofRFID and anti-collision. It acquires comprehensive advantage in securityproperties, anti-attack ability，low cost, execution rate, anti-collision and so on，and we still have a very urgent task on it.