Design And Optimization Of RFID Tag File System Based On Red-Black Tree

RFID technology has been the popularization and development with the rapid development of internet of things and formulation of RFID standards, not only promote the development of the embedded systems, but also makes life more convenient and intelligent. The process of RFID technology to develop, the emergence of many characteristic electronic tags, due to the short identified distance of passive RFID tag, poor security and other shortcomings, so that the active electronic tags have more future potential.The national standard- GB/T 28925-2012 of the 2.45 GHz active RFID air interface protocol was issued by the relevant departments in 2012, wherein the file system is an important part of the air interface protocol standard, and its design and implementation affects the performance of the entire electronic tag. Through the analysis of the RFID technology and the embedded file system, the thesis designs and impletes the RFID tag file system in accordance with the demand of file system in the standard. In order to further improve the real-time of reading and writing file data, combined with the efficient search feature of red-black tree algorithm, and the real-time optimization carried out for the tag file system.Firstly, the thesis conducts a in-depth study of the RFID technology and a variety of the current popular file system, to select the FAT file system having more mature technology as a design model, according to the demands of file system in the air interface protocol standard, to design and implete a streamlined RFID tag file system.Secondly, in order to achieve the target of further improving the reading and writing speed of the RFID tag file system, by summarizing methods to improve the reading and writing speed in the existing embedded file system. The thesis proposes a solution of real-time optimization for tag file system by using red-black tree. this solution finds the factual basis of a large of contiguous free data blocks and contiguous occupied data blocks by analyzing FAT table, to establish the node model for representing continuous data blocks, combined with the red-black tree, this kind of high efficient index structure, to design the red-black trees of the free area and red-black tree of the occupied area by regarding continuous data blocks as the red-black tree node information. The above optimization method make block information required by file operation be found in the established red-black tree, perfectly improving the reading and writing speed, and completing the real-time optimization of the RFID tag file system.Finally, to build the system of the practical application, under the premise of readers and tags having achieved communication, the thesis verify the basic operating function of the file system. On this basis, respectively to carry out comparative analysis among the tag file system optimized by red-black tree, optimized by B tree and pre-optimized, to test the improvement of real-time.