Uhf Read-write Device Design Based On Fpga

The Internet of Things is one of the ever important high-tech industries which will bring a most promising market with about one trillion-dollars in future years. As a key technology of IOT, RFID technology has got more and more attention from both governments and IT R&D personnel recently. UHF RFID is not only a hot spot of research and application of RFID technology, but also a popular application of IOT. Developing an UHF RFID reader with high-performance can promote the broad development of RFID technology, and at the same time make contribution to the application of IOT technology.Meanwhile, taking the design of software and hardware implementation as a guideline, this dissertation covers a lot of aspects in UHF RFID reader, for example, the base-band data processing, RF circuit and anti-collision algorithm as well.To begin with, the important RF circuit parameters are illustrated and the design specifications of the UHF reader are pointed out after analyzing the ISO/IEC18000-6C protocol. RF front-end circuit implementation in this design has the advantages of low cost and easy testing. The chip Si4133-BT is used as the LO of the UHF reader to meet frequency hopping and spreading in communication. In order to get the performance of20dBm in output power energy, RF2173and RF2376is used to build two-stage power amplification. The receiver of the UHF reader adopts zero-IF receiver architecture and the comparator LM319is uesd to implement the data converter.Secondly, the base-band circuit in this dissertation is designed in Verilog HDL language and implemented on the chip EP1C12QC8N of Altera Corporation. The base-band circuit consists of coding module, decoding module, communicating module and so on, are designed using the finite state machine(FSM). After the simulation of above modules in the ModelSim, the program is downloaded to the UHF reader hardware platform to carry out the validation process.Thirdly, several anti-collision algorithm which derived from ALOHA are studied, the mathematical model of each algorithms are built and simulation of system efficiency under different algorithms is implemented by Matlab. After the research of dynamic frame slotted ALOHA anti-collision algorithm and tag number estimation algorithm in ISO/IEC18000-6C, the new tag number selection algorithm is put forward which will promote the system efficiency to about33%in simulation environment.Finally, the test of the RF circuit and data extraction is carried out successful for the new reader. Through the analysis of data and the comparison of images, this design gets the conclusion that the designed UHF reader has a good performance and meets the desired design requirements well.