Research And Design Of The Key Modules In Frequency Synthesizer In UHF RFID Receiver

Radio frequency identification technology is proposed from the1990s, the ongoingdevelopment of its applications are increasingly being used. In this context, UHF RF front-endcircuit based on phase-locked loop frequency synthesizer circuit is important, it can provide a largenumber of accurate and stable reference frequency reference into a corresponding magnificationrelations frequency signal to the transceiver.This paper first introduces several common realization method based on the basic principles ofthe PLL frequency synthesizer, one for UHF RFID frequency synthesizer circuit, and behaviorModeling and Simulation. Based on the frequency synthesizer overall system requirements, thepaper discusses the performance requirements of each module. PFD module, the article discussesedge triggered the PFD, designed a dynamic structure of the D flip-flop the PFD. PFD reset delaycircuit optimization, to overcome the dead zone of the PFD and CP, has fast simple structure.Folding common source of of gate operational amplifier and the self-bias reference current source,introduced in the CP circuit reduces the current mismatch problem, so that the CP charge anddischarge current height matching, with speed, the charging and discharging currents and goodmatching characteristics. The divider circuit This paper presents a divider circuit based on dualmodulus divider cascade structure, divider circuit can be more flexible than larger scalability, joinedthe sigma-delta modulator fractional divider. Analog IC layout design requirements andperformance characteristics of the respective circuit layout of the PFD, CP and divider. And givenunder CMOS0.18μm process conditions, the module circuit simulation before and after thesimulation results. Discriminator the fight phase detector circuit of the various logic functionscorrectly, the CP in the0.2V to1.6V output voltage range of the mismatch is less than0.1μA,divider circuit frequency ratio of between64to127stars added The third-order MASH1-1-1modulator for fractional frequency.