The Research On Performance And Application Of RFID System Based On Listed-reading Mode

In recent years, RFID (Radio Frequency Identification) has been developing very fast, and has been used more and more widely. RFID is playing an increasingly important role in either production or life. As one of the most important technologies of data collecting, RFID can identify the information of tags quickly and accurately, and its most prominent feature is the multi-tag identification. But, when a mount of tags within the reading area attempt to communicate with the reader simultaneously, there will be a tag-collision problem. Now, the main solutions to this problem are Binary Search algorithm and the ALOHA algorithm. Both of the two algorithms need to read the tags that are within the reading area one by one according to the corresponding algorithm in the reader. But when the number of the tags is large, the overhead and the delay of the two algorithms are obvious.This paper proposes a novel reading mode for RFID readers, Listed-reading Mode. Comparing with the traditional reading mode, the Listed-reading Mode directly skips the process of anti-collision algorithm and read tags within the reading area. But not all the tags within the reading area are likely to be identified, only the tags whose UID have been already in the reading list will be identified. Readers will generate a address list and save the UID of the tags that are going to be identified. Readers read the tags whose UID in the list according to some certain rules (for example, by the order).Comparing with the traditional cogitation of anti-collision, the Listed-reading Mode will not identify all the tags within the reading area with certain algorithm passively, it means that for traditional anti-collision cogitation, reader will bring any tags that belong to system in the algorithm, on the other hand, reader can only decide the reading order according to the algorithm, and the complicated algorithm process also increase the overhead of the system. As to Listed-reading Mode, reader will skip the process of traditional anti-collision algorithm, but that requests the reader have UID of the tags, it means that reader has the reading initiative for Listed-reading Mode. Reader will be issued identification tags with unique identification number (UID) of the query command, the tags will receive this command, the UID in the command and the UID of the tags do XOR operation if the result of one certain tag is zero, then it means that the tag is the one which the reader need to identify. If the reader trying to read the tag list fails, in this paper two sub-modes, Substitute Reading Mode and Cycle Reading Mode are proposed. According to different situation, two sub-modes can be used in combination, forming Nested Reading Mode, the corresponding flow charts are given for illustration.To prove the superiority of the Listed-reading Mode, query times,transmission delay and system efficiency are simulated in this paper, and Binary Search Algorithm that is similar to Listed-reading Mode in working principle is simulated and analyzed in comparison with the Listed-reading Mode. The result of the simulation shows that the performance of the Listed-reading Mode is better than the traditional Binary Search Algorithm in query times,transmission delay and system efficiency. At the end of this paper, open bookshelf management and storage management are set as background, applications of the Listed-reading Mode and the sub-modes are designed to solve practical problems in reality.