简介:Anovelfibergratingvibrationdemodulationsystem,basedon2×2and3×3couplers,isdesigned.Basedonthephaseunwrappingalgorithm,thethree-wayasymmetricaloutputofthe3×3coupleranddemodulationstatecharacteristicsofthesystemwhenthevibrationsignalincludeshighharmonicwavesareanalyzedinsimulations.Theresultshowsthatwhenthethree-wayoutputisasymmetrical,themaximumdeviationofdemodulationsignalis1.625%,andwhenthevibrationsignalincludeshighharmonicwaves,themaximumdeviationofdemodulationsignalis0.9%.Thecorrespondingexperimentisconducted.Theexperimentalresultshowsthatthedynamicresolutionofthesystemis25.22nε/Hzwhenthevibrationpitchis5.5Hz.
简介:A2.4GHz0.18μmCMOSgain-switchedsingle-endLowNoiseAmplifier(LNA)andapassivemixerwithnoexternalbalunfornear-zero-IF(IntermediateFrequency)/RF(RadioFrequency)applicationsaredescribed.TheLNA,fabricatedinthe0.18μm1P6MCMOStechnology,adoptsagain-switchedtechniquetoincreasethelinearityandenlargethedynamicrange.ThemixerisanIQ-basedpassivetopology.MeasurementsoftheCMOSchipareperformedontheFR-4PCBandtheinputismatchedto50Ω.CombiningLNAandmixer,thefront-endmeasuredperformancesinhighgainstateare:-15dBofS11,18.5dBofvoltagegain,4.6dBofnoisefigure,-15dBmofⅡP3,-85dBmto-10dBmdynamicrange.Thefullcircuitdrains6mAfroma1.8Vsupply.