Research And Design Of Signal Sources For Chipless Multi-tag RFID

Radio Frequency Identification(RFID)is a new automatic identification technology,which has the advantages of non-contact,data security,and high communication speed.A typical RFID system consists of two components: a reader and a tag.In a chipless RFID system,a chipless tag is used as a passive detection object,and an RFID reader is required to send an RF query signal to make it resonate and reflect the echo to comple te the tag identification.The RF signal sent by the RFID reader is generated by the RF signal source.Therefore,the research on the signal source has important significance in chipless RFID.This paper mainly studies the chipless multitag RFID signal sou rce,and designs a signal source with the output frequency from 1GHz to 8GHz.First,the important role of the signal source in the RFID system is analyzed.Then the basic knowledge of the signal source is introduced,and the circuit composition,working principle and mathematical model of each part of the phase-locked loop frequency synthesizer and frequency multiplier are systematically expounded.Finally,through the analysis of the requirements of the chipless RFID system,the design indicators of the sign al source are given,and the overall design of the signal source is determined.The design consists of three parts: frequency synthesizer,frequency multiplier,and amplifier.Firstly,the ADF4350 chip is used to build the frequency synthesizer system.The system is verified by ADIsim PLL software,and the schematic diagram,PCB version and actual circuit design of the system are completed.Secondly,the feasibility of the Schottky diode frequency multiplier is verified by the circuit simulation software Agi lent ADS,and the actual circuit fabrication is completed.Then according to the input signal requirements of the frequency multiplier,a suitable amplifier circuit is designed and completed.In the end,the three parts constitute a complete signal source,and the signal source is subjected to experimental testing and results analysis.The test results have reached the expected design index.