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The Internet of Things (IOT) is built on the traditional Internet, but differs in that itconnects a huge number of physical things as user ends. IOT has been considered as thethird wave in the world information industry and receives great attention worldwide.One key technology in IOT is Radio Frequency IDentification (RFID). RFID uses radiofrequency wireless signals to achieve non-contact transmission of data, for the purposeof automatically identifying and tracking goods, or sharing information. Compared withthe traditional barcode identification technology, RFID offers advantages of stronganti-pollution ability, high security, huge memory capacity and long distanceidentification of multiple tags. In a word, RFID is indispensable in IOT. Unlike otherfrequency band RFID, Ultra High Frequency (UHF) RFID system has long reading andwriting distance, high data rate, and electronic tags don’t need to be separated frommetal. As a result, UHF RFID can be widely applied in supply chain management,production automation, air parcel management, container management, logisticsmanagement etc.In this thesis, a UHF RFID reader is designed and implemented based on ISO/IEC18000-6B standard. Such a UHF RFID reader receives and analyzes the commandsfrom the host computer to communicate with electronic tags. It can read, write, andinventory tags. Besides, it supports multi-tag operations.For the hardware design, a32-bit microcontroller with embedded ARM Cortex-M0core is chosen. The baseband circuit consists of control circuit, power supply circuit,reset circuit, RF interface circuit, host interface circuit, debugging circuits, etc. RFcircuit uses ADI’s RF transceiver ADF7020.For the software design, C language is adopted for modularized programming. Thesoftware consists of main program module, protocol processing module, host interfacemodule, RF control module, and system bottom module. The protocol processingmodule is the core module of the software. It implements encoding, decoding andchecking the baseband signals and supports anti-collision protocols according toISO/IEC18000-6B standard. Traditional UHF RFID reader is implemented with FPGA or UHF RFID ASIC,while our reader only uses general RF transceiver and software to implement basebandsignal processing so that it has the advantages of small size, low power consumptionand low cost, which are desirable in a variety of practical applications.
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