Research On Air-interface Protocol Of UHF RFID

RFID(Radio Frequency Identification),is a new high-tegh which was developed in the end of the 20th century and has obtained rapid development and widespread application in the past few years With its technical maturity and the commercialization application demand,the standard has become the main factor of hindering its development.This paper gives a issue on the multi-tag's anti-collision. link modulation and tags' identification rate,which are concerns of UHF standard.The paper carries on a show to the RFID extant standards.On the basis of the analysis of existing anti-collision algorithms,to raise the identification efficiency of aloha,the paper analyses the number of collising tags in different time-slots,construcs a mathematics model of colliding tags,analyses the best use of time-slots' using rate,and gives an algorithm of multi-tag's rapid identification.The algorithm reduces the redundant time-slots and the numbers of the Query commands,so reduces the identification time.Gives a simulation to the algorithm by Matlab.It analyses the links' encoding and modulation option of ISO/IEC 18000-6C. Carries on a comparison to the three modulation modes of the forward link.It achieves the waveform and spectrum by Matlab,points out the advantage and use necessity of PR-ASK.It analyses the digital baseband signal's spectrum of RFID system,educes the relation between the bandwidth and the transmission speed.Analyses the RFID condition of UHF respectively on the radio environments of American and Europe. Establishes the tag-identification model,analyses and calculates the maximum tag-identification velocity of American and Europe.