Research And Application Of Anti-Collision Algorithm For RFID System

Radio Frequency Identification (RFID) technique using the space coupling characteristicof radio frequency signal to achieve non-contact automatic identification of the target object,because of its advantages such as large data storage, short identification time and high datasecurity, etc, RFID has got a rapid development and become very popular in public service,manufacturing, logistics, supply chain management and many other fields. As a result of itsunique superiority, RFID is bringing a new technical revolution in the field of automaticidentification, many countries around the world have invested a lot of time and energy toresearch and promote this technology.Although RFID has many advantages, but there are some problems that restrict itsdevelopment, such as the tag cost, system compatibility and anti-collision problem, etc. Thispaper mainly focuses on the anti-collision problem of RFID system, by analyzing andsummarizing the existing anti-collision algorithms, we have made some new design for RFIDtag anti-collision algorithm, and proposed our new anti-collision algorithms.Firstly, RFID system is briefly introduced, and then focuses on the anti-collision problemof RFID system, including the definition of collision, the judgment of a collision and themajor existing anti-collision algorithms. Some typical algorithms which belong toALOHA-based algorithm and tree-based algorithm are chiefly introduced, includingP-ALOHA, S-ALOHA, FSA, DFSA algorithm and binary search algorithm, binary treealgorithm and query tree algorithm together with those algorithms that based on them.Secondly, according to the deficiency of query tree algorithm in the practical application,we combine the idea in collision tree algorithm and present a new anti-collision algorithm--Fast Query Tree (FQT) algorithm. FQT makes full use of the first collided bit in the reader’sreceived information, and reader splitting the respond tags according to this bit. There are twocounters in each tag which remembered the reader’s query history, therefore reader do notneed to transmit the whole query prefix, instead, reader just transmit the last bit of currentprefix. Simulation results show that FQT outperforms query tree algorithm and collision treealgorithm in communication overhead and identification speed.Thirdly, based on FQT, we proposed the Improved Collision Tree (ICT) algorithm, byadding a flag in each tag, ICT avoid the idle cycle in the identification process which mayexist while using FQT, and improved the performance again. The analysis of ICT and thesimulation results show that ICT outperforms CT in those situations that tag’s ID has somecommon prefix.Finally, this paper describes the application of RFID technology in the supply chainwarehouse management, first, we analyzed the business processes of traditional warehousemanagement and summarized the existing problems that need to be solved. Then, we designedthe operation processes of warehouse management based on RFID technology, and verifiedthe anti-collision performance of the ICT algorithm in the circumstance of supply chainwarehouse management.