Antenna Design Guide_EN_v1

AntennaDesignGuideAntennaDesignGuideTableofContents1Introduction...........................................................................................................................52AntennaInterfaceStage.......................................................................................................6ChipOutputImpedance..................................................................................................................7EMCFilter.......................................................................................................................................8MatchingNetwork...........................................................................................................................9CapacitiveVoltageDivider............................................................................................................10TrimCapacitors.............................................................................................................................10Antenna.........................................................................................................................................103AntennaDesign..................................................................................................................11Boundaryconditionandsimulationmodel....................................................................................11Simulationresultsoftheparametersweep...................................................................................12Conclusions...................................................................................................................................164AntennaParameters..........................................................................................................17NetworkAnalyzerPreparation......................................................................................................17ParameterMeasurement..............................................................................................................17AntennaEquivalentCircuit............................................................................................................195AntennaMatching..............................................................................................................25MatchingTool................................................................................................................................25Simulation.....................................................................................................................................29Models...........................................................................................................................................29Results..........................................................................................................................................316DesignVerification.............................................................................................................34MeasurementofPCDRFanalogparamters.................................................................................34VerificationoftheQ-factorintheTimeDomain............................................................................35VerificationoftheQ-factorintheFrequencyDomain...................................................................35MeasurementoftheTargetMatchingImpedance........................................................................36Copyright...........................................................................................................................................38Disclaimer..........................................................................................................................................38AntennaDesignGuideAcronymsandAbbreviationsAlistofacronymsusedinthisdocumentcanbefoundinthetablebelow.Table2:AcronymsusedinthisDocumentAcronymDescriptionRFO1,2AS3911antennadriveroutputpinsRFI1,2AS3911receiverinputpinsTxTransmitsignal(fromRFOtoantenna)AntennaDesignGuideAcronymDescriptionRxReceivesignal(fromantennatoRFI)LEMC1,2InductoroftheEMCfilterCEMC1,2CapacitoroftheEMCfilterCS1,2SeriescapacitorofthematchingnetworkCPParallelcapacitorofthematchingnetworkRQParallelresistorusedfortheQ-factoradjustment(calculated)LANTAntennainductance(measured)CANTParasiticantennaparallelcapacitance(calculated)RPANTTotalantennaparallelresistance(calculated)fworkNFCOperatingfrequencyof13.56MHzfresAntennaself-resonancefrequency(measured)RSDCAntennaseriesresistance(measured)RP@fresAntennaparallelresistanceatself-resonance(measured)KSkineffectcorrectionfactor(calculated)RP@fworkAntennaparallelresistanceatoperatingfrequency(calculated)RPDCAntennaparallelresistanceconvertedfrommeasuredseriesresistance(calculated)RTParallelresistancefortargetQ-factor(calculated)QAntennaQ-factor(calculated)HardwareandSoftwareRequirementsInordertousetheprovidedAntennaMatchingTool,performantennameasurementsandverifythedesignthefollowingh