Research And Implementation Of Base Band Controller For RFID Tag Chip

RFID is abbreviation of Radio Frequency Identification. As a kind of new automatic recognition technology, RFID has wide development prospects. It is important to research on it. RFID comprises of three parts: Reader, Tag and application system. The tag is on the surface of object, the electronic data is stored in tag. Reader brings forward of the request to tag, tag answers for the request and gives reply to reader.The design and implement of base band controller of ultra high frequency tag with the characteristic frequency of 900MHz are described in this paper. The base band controller can be implemented either by finite state machine or by MPU. The reason why choose structure base on finite state machine and compose of band base controller is explained here.CRC-5 or CRC-16 is widely used in CRC checking. According to the standard of ISO/IEC 18000-6, a further transformation on the calculated CRC is made, 5 bits or 16 bits CRC is adopted according to the length of command. Two ways of compatible with CRC-5 and CRC-16 are described and compared in this paper.Finite state machine controller is the core of base band controller; it executes the request transmitted by reader and gives reply to reader based on current state. The process flow of every state is described in this paper. The performance of base band controller is decided by the finite state machine controller .Therefore, some ways of optimization are introduced in this paper.The issue of low power is widely focused on. As passive tag, if it costs energy too much, it will not work well. Some ways of low power in 900MHz tag are described in this paper.