The Critical Modules Research On Digital Baseband Of UHF RFID Reader

Internet of things(IOT) technology which is known as one of strategiccommanding point in another round economic and technology development, isbecoming an important part of the rising industry. As the core perceptive technologyof IOT,radio frequency identification technology(RFID) is getting more and moreattentions. Comparing to the low frequency RFID system,the UHF RFID system hasadvantages in the identification distance read-write speed etc.and is widely used in thetransportation and intelligent agriculture in recent years.In order to reduce the costand power consumption,the research of UHF RFID reader miniaturization isunderway.This thesis comes from the UHF and Microwave RFID reader chip R&Dproject.The reader digital baseband frame structure and the key module circuit designand FPGA validation are proposed based on the study of the ISO/IEC18000-6Cprotocol.First this thesis introduced the electromagnetism principles of RFID andanalyzed the ISO/IEC18000-6C protocol The reader digital baseband system isdivided into three parts based on the protocol analysis,the sending module, receivingmodule and the linking-control module,In order to determine the system architecturefeasibility the Simulink modeling and simulation was used in the send and receivelinking to design the data encoding and filter. Then the specific implementation ofdigital baseband key circuit was elaborated. We realized the multi-rate PIE encodingand FM0/Miller decoding function by analying the linking codearchitecture,optimized the traditional accumulation structure in shaping filter througnusing shifter register,CSD coding to reduce the resource utilization.To reduce theimpact caused by the channel noises which have influnce on the docoding module injudging symbol length,we proposed a method to auto adjust the length of symbol inthe deserializer.The linking control module is implemented througn the finite statemachine and uses three-wires serial communication interface) based on DigRFstandard to communicate with external module.The simulation and FPGA verificationof key module in digital baseband are completed using ModelSim6.5andEP2C8Q208C8N of Altera.Results show that the digital baseband conforms to therequirements of ISO/IEC18000-6C standard, and provide design reference for realization of UHF RFID reader SoC.