An Optimized Combined Anti-collision Algorithm Based On Multi-state Quad-tree And Frame Slots

RFID(Radio Frequency Identification) technology is widely used in many fields, such as intelligent buildings ? transportation systems ? social security ?manufacturing ? supply chain management and so on. Using various standards ?collision of tags are the main problems for manufactures. These problems always influence the spread of supply chain system and transportation system. So it has great significance to research reader's design in multi-protocol and the algorithm of anti-collision's optimizing.The current anti- collision algorithms used in RFID system were analyzed and compared, an optimized combined anti-collision algorithm based on multi-state quad-tree and thought of the new frame slots was presented. In proposed algorithm,labels were matched by prefix in response to the reader, split into four returning slots,divided until fully identified when a reader communicated with labels. The following work has been done in this paper:(1) First it introduced the background of RFID system, the development and application at domestic and overseas for RFID technology. Secondly it summarized the system's composition ? working principle ? classification. Thirdly it analyzed several algorithms used in anti-collision problems.(2) For radio frequency identification system has multiple tag reader collision problems around, the analysis and comparison of several binary search algorithms,combing the thought of ALOHA algorithm, and introduced ideas of multi-state quad-tree and frame slots in order to optimize binary algorithm.(3)It described the analog processing that a reader identify tags simulated by MATLAB, then compared the difference between the enhanced algorithm and other binary search algorithms in identifying times and command bits, and simulation analysis indicated that the enhanced algorithm primly optimized performance than others.In summary, an enhanced algorithm was superior to others proved by theory and simulation analysis.