Implementation And Research Of UHF RFID Reader Based On AS3992

As a means of information collection and identification, Radio Frequency Identification(RFID) technology automatically obtains the target object’s information and data throughradiofrequency signal. This identify process has high reliability, antijamming and security.Compared with low Frequency and high Frequency RFID reader, the ultra high frequency(860MHZ to960MHZ) RFID reader designed in this paper has a further higher recognitiondistance, can be read and written fastly and can penetrate nonmetallic, etc. It has a broadprospect in the application such as the vehicle transportation, warehousing and other logisticsmanagement, and it is the current research hot spot. This paper designed a UHF RFID readerusing the high integration radio frequency chip AS3992. The reader can be compatible with avariety of standard protocols and has a long reading and writing distance，what is more, it haslow power consumption and small volume. The main work is as follow:1.Hardware system design of the readerThe hardware design includes Master control module design,RF module design and PCBdesign.1)Master control module design: this design choose the C8051F340single chipmicrocontroller as the MCU, it has the advantage of fast processing speed, high integrationand low cost;C8051F340adopted USB interface to communicate with PC, and communicatedwith the RF module with parallel interface.2)RF module design：This design choose AS3992as RF chip of the RF module, AS3992chip has the characteristics of low power consumption, simple peripheral circuit design, smallvolume; transmission circuit adopted external power amplifier to enhancing the reading andwriting distance, receiving circuit used zero intermediate frequency receiver to overcome thezero effect, peripheral circuit design aimed at improve the quality of signal to ensure signaltransmission.3) PCB design: for PCB design, this paper chooses reasonable PCB layout and wiringrules, and transmit the signal with micro strip line and has designed50ohm impedancematching, in order to solve the problem of the electromagnetic compatibility andelectromagnetic interference of radio frequency circuit, to ensure the accuracy of signaltransmission.2. Control software design of the readerBased on the recognition layer of ISO18000-6C protocol, this paper designed the systemsoftware architecture, and made software implementation of the operation from reader to tag:including reading single tag, writing tag, lock tag and killing tag.What is more, this paperAntiCollision design: adopting the Q value adjustment algorithm to improve the anticollisionrate when reading multiple tags at the same time.Based on AS3992RF chip, this paper researched the ISO18000-6C protocol in depth, completed the hardware system and control software design of the RFID reader. The testproved that the reader can smoothly read and write the electronic tags.