Simulación y medida de tarjetas sin contacto

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ESCUELA TÉCNICA SUPERIOR DE INGENIERÍA DE TELECOMUNICACIÓN

UNIVERSIDAD POLITÉCNICA DE CARTAGENA

Proyecto Fin de Carrera

Simulación y medida de tarjetas sin contacto

AUTOR: Sandra Montoro Almendral DIRECTOR: Nikola Gvozdenovic, María Victoria Bueno y Christoph Mecklenbräuker

Julio / 2014

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Enestatesisseestudiael omportamientodelastarjetasdeproximidad(PICC)queoperanen

labanda de altafre uen ia a 13.56MHzusando elsimulador Advan ed DesignSystem (ADS)

así omomedidas reales.

EstasPICCsontarjetaspasivasalimentadasporlaantenadelle tormediantea oplomagnéti o

y onsistenenunabobinadeantenay iertos omponenteslinealesynolineales omoresisten-

ias,diodos y ondensadores. Uno de los objetivos de este trabajo era analizar omo algunos

deloselementosafe tanalfun ionamientodelasPICCtantoensimula iones omoenmedidas.

Estetrabajo ha sido organizado en uatro apítulos. En elprimer apítulo aporto una visión

generaldelaopera ióndelasPICCsegúnelestándarISO/IEC14443. Enestaprimerase ión

tambiensepresentael ir uitoempleado omomodeloparalasimula iónymedidadelasPICC.

Enelsegundo apítulo, lasPICC de referen iaseanalizan tanto ensimula iones omoen me-

didas. Como se ha men ionado anteriormente, para las simula iones se empleó el simulador

ADSde Agilent. En primerlugar se denen los parámetros que van a ser variados yelrango

devaria iónde los mismo.

La orriente ytensión de entrada sonanalizadas tanto en tiempo omo en fre uen iaen fun-

ión de los diferentes omponentes variados. El voltaje re ti ado, que es el que nalmente

empleanlas PICCparasu fun ionamiento, tambiénesestudiado. Por otraparte, seempleala

representa ión delas urvasde Lissajouspara elestudiode lanolinealidad del hip.

Para lasmedidas se diseño el ir uito en Eagle yposteriormente se onstruyó en un PCB.El

pro esosedes ribe onmásdetalleen2.2.1 . Lasmismasseñalesqueenlassimula ionesfueron

analizadasysemuestran en 2.2.2 .

Por último, se ha euna ompara ión de los resultados obtenidos en simula iones y medidas.

Aunque las simula iones se realizaron en ADS, todos los datos fueron exportados y para las

ompara ionesseempleóMatlab. Alnodisponerdesondasdiferen ialesnidesondasde orri-

entesepuede observarquelasmedidasdela orrienteyelvoltajere ti adosonmásruidosas

quelasobtenidas enlasimula ión peroseobserva queambaspresentan lamisma tenden ia.

En el ter er apítulo, se realizó un test denido en elestándar ISO 10373 sobre un PICC de

referen iarealusandounsimuladordele turallamadoTestPCDassemblypropor ionado por

laempresaNXP.

Enel uarto yúltimo apítulosein luyen las on lusiones yse omenta laperspe tivafutura

eneste ampo.

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Ihavea knowledged all thesour esofinformation whi h have been usedinthethesis.

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I would like to thank my advisors Univ.Prof. Ing. Dipl.-Ing. Dr.-Ing. Christoph Me klen-

bräukerandDipl.-Ing. NikolaGvozdenovi fortheirguidan eandsupportduringthisdiploma

thesis.

I owe my gratitude to Dipl.-Ing. Dr.te hn Robert Langwieser for his patien e and for trans-

mittingpart ofhis wide knowledgeon RF ir uitdesign and measurement.

Iwouldliketo thankGeraldArtner andMartinMayer, whofromthebeginninghelpedmeget

involved in the daily routine of the institute making the experien e more enjoyable. Spe ial

noteof appre iation to my friend Martin Mayer for several enlightening dis ussions in whi h

hegenerouslyshared withmehis expertiseon Matlab oding.

Iamalso verygrateful to theindustrialpartner RalphPrestosand Dipl.-Ing. Dr.te hn Lukas

W.Mayerfortheir ontinualinterestintheprogressofthisworkandfor alwaysbeingready to

help.

Myappre iation andthanksto myparentsfor theirun onditional supportand onden eand

tomysister for always giving afunnyperspe tive onwhat shethought I wasdoing.

Intheend, Iwouldlike to thank my friendsfor being there even from thedistan eand espe-

iallymyboyfriendJorge forhis supportandfor allthe timehespenton online onversations

to heerme up.

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InthisthesisIinvestigatethebehaviorofProximityintegrated ir uit ard(PICC )operatingin

theHigh Frequen y (HF)band at 13.56MHzusing Advan edDesign System(ADS) simulator

andalso real measurements. Those PICC arepassive tagspoweredbythereader antenna via

indu tive oupling and onsistof a oil antenna and ertainlinear andnon-linear omponents

su h as resistors, diodes or apa itors. One of the goals of this work was to understand how

someof theelementsae t theoperationof thePICCin both simulation and measurement.

This work was organized in four hapters. In the rst hapter I give a brief overview of the

operation ofthe PICC a ording to theISO/IEC 14443 standard and introdu e thereferen e

PICC ir uit.

Inthese ond hapter,referen ePICCisanalyzedbothinADSsimulationandinmeasurement.

For themeasurements, areferen e PICCis built ona Printed ir uit board (PCB )in2.2.1 .

Inthethird hapter referen ePICC istested ina reader emulator alledTest PCD assembly.

Inthefourthand nal hapterI give on lusionsand outlook fora futurework.

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1 Introdu tion 1

1.1 Operating prin iple of onta tless hip ardsand requierementsof ISO14443 . 1

1.2 Referen e PICC ir uit . . . 4

2 Simulation and measurements 6 2.1 Chip ardsimulation . . . 6

2.2 Chip ardmeasurements . . . 16

2.2.1 PICC design and onstru tion . . . 16

2.2.2 Setup andresults . . . 18

2.3 Analyzing simulationand measurementsresults . . . 22

3 TestPCD assembly 29 3.1 Des ription . . . 29

3.2 Referen e PICC test usinga reader emulator . . . 32

4 Con lusion and Outlook 40

List of Figures 41

Bibliography 43

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Introdu tion

Radiofrequen yidenti ation (RFID)hasbeen usedinseveralpra ti al appli ations, su h as

improving supply hain management, tra king household pets, a essing o e buildings, and

speedingup toll olle tion onroadways.

Compared to its prede essor, the proximity ard, a onta tless ard provides mu h greater

se urityand ontains 100times the datastorageof atraditional proximity ard.

Conta tless hip ards are usedin variety of appli ations, e.g. for identi ation, inbiometri

passports, redit and bank ards et . and they are developed to be read without a reader

devi eusingRFID.

Inthisrst hapterthestandardsusedandthereferen ePICC ir uitareintrodu ed. Further-

more, the operation prin iple of onta tless ards is explained as well as the ommuni ation

interfa e between ard andreader.

Themainpart ofthe hapterin ludes thedes riptionofthereferen ePICC ir uit denedin

ISO10373-6 whi h hasbeen usedasthebase modelfor simulationsand measurements.

1.1 Operating prin iple of onta tless hip ards and

requierements of ISO 14443

The omponents of an RFID eld are a transponder or tag and a reader. The intera tion

between atransponder hipand atransponderantennadependsonseveralparameterssu has

the designof both oils orthe operationfrequen y and ithasbeen investigated in[1℄.

Inthis workwe will fo uson thenonlinearee ts produ e onthetransponder hipprodu ed

whensome parameters ofits omponents aremodied.

Theoperatingprin iple of onta tless hip ards 1.1is basedon magneti oupling. It means

thatthe transponder and thereader antenna are oupled by themagneti ux through both

oils. An AC voltage is indu ed in the ard loop antenna and the PICC onverts this AC

voltage into DCinorder topowertheIntegrated ir uit(IC).

Atagtypi ally onsistsofanele troni mi ro hipand hip antennadesigned toallow ommu-

ni ationswitha reader [2℄.

RFIDtags fall into two ategories, a tive tags, whi h maybe totally or partially powered via

its own battery supply, and passive tags, whi h obtain power from the signal of an external

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work.

Figure 1.1: Operatingprin iple onta tless hip ards

ISO 14443 is an international standard for proximity or onta tless smart ard ommuni a-

tionwhi hdes ribeshow onta tless ardsandterminals shouldwork toensure industry-wide

ompatibility. For example itplays akey role inidentity,se urity,payment,mass-transit and

a ess ontrol appli ations.

ISO 14443 is a four-part international standard for Conta tless Smart Cards operating at

13.56MHz in lose proximity with a reader antenna. PICC are intended to operate within

approximately 10 mof the readerantenna[4 ℄.

Part 1: denessize and physi al hara teristi s ofthe ard.

The PICC antenna shallnot ex eed 86mmx54mm x3mm.

The PICC should operate as intended after ontinuous exposure to a magneti eld of

an average levelof 10A/mrmsat 13,56MHz. Theaveragingtimeis30 se ondsandthe

maximumlevelof the magneti eldislimitedto 12 A/mrms.

Part2: denestheRadioFrequen y(RF)powerandsignalinterfa e. TypeAandType

B ards arealso dened inthispart.

The PICCshalloperateasintended ontinuouslybetween

H min = 1.5A/m

^and

H max = 7.5A/m

^.

Two ommuni ationsignalinterfa es, TypeAandTypeBaredes ribedinthestandard.

TheProximity ouplingdevi e(PCD )shallalternatebetweenmodulationmethodswhen

idling before dete tingthepresen eof aPICC of Type Aor TypeB.

ThePICC shallbe apableof ommuni ationto thePCDviaan indu tive ouplingarea

where the arrier frequen y is loaded to generate a sub arrier with frequen y

f s

^. ^The

sub arrier shallbegenerated byswit hing aload inthePICC.

The frequen y

f s

^of ^the ^sub
arrier ^shall ^be

f c

^/16 ⁽ ⁸⁴⁸ ^kHz). Consequently, during initializationandanti ollision,onebitdurationisequivalentto8periodsofthesub arrier.

After initialization and anti ollision, thenumber of sub arrier periods is determined by

thebit rate.

The PICC shallgenerate asub arrier only whendatais tobe transmited.

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In order to dete t PICCs whi h are in the operating eld, a PCD shall send repeated

Request ommands. When a PICC is exposed to an unmodulated operating eld (see

ISO/IEC 14443-2) itshall be ableto a ept arequest within5 ms.

Part4: denes the high-level datatransmissionproto ols for Type A and TypeB. The

proto ols des ribed inthis part areoptionalelementsof thestandard.

Two ommuni ation signal interfa es Type A and Type B have been mentioned before. In

table1.1the dieren esbetween themaresummarized.

Table 1.1: Type A andB ommuni ation interfa es

Type A Type B

Downlink Modulation (PCD

toPICC)

100% ASK modied Miller

ode

10%ASKNRZ ode

Signal/noiseratio Veryhigh (30%noise tol.) Low (3%noise toleran e)

Uplink Modulation (PICC to

PCD)

Load modulation, ASK

Man hester ode

Loadmodulation,BPSKNRZ

ode

Anti Collision Binary Sear h method Timeslot method

Speed no dieren e between TypeA and Type B

Se urity no dieren e between TypeA and Type B

Power(energye.) no dieren e between TypeA and Type B

Asan example, the ommuni ation diagram between the reader and a Type B ardis shown

in1.2 To initiate the ommuni ation thereader sends a Request ommand (REQ ) ommand

to thePICC.

ForTypeBsignalinterfa e,thePCDis ontinuouslytransmittingtheunmodulated13.56MHz

RF arrierfrequen y whennot transmitting data to the PICC.

ThePCD modulatestheamplitudeofthealternatingmagneti eldstrengthwithmodulation

pulsesinorderto transmit datafrom thePCDto the PICC.

ThePICC loadsthe alternating magneti eld witha modulated sub arriersignal(loadmod-

ulation)inorderto transmit data fromthePICC to the PCD.

WhenPCD dea tivatestheRFeld, PICC should be dea tivatedafter nolonger than 5ms.

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1.2 Referen e PICC ir uit

Togetherwith standard ISO14443, Part6ofthe standard ISO10373 [5℄hasbeen also onsid-

ered. It denestest methods for identi ation ardsand spe iesthe referen ePICC ompo-

nents and onstru tion.

Ingure1.3the refere ePICC ir uit isshownand itsparts arelabeledand des ribed below.

Figure 1.3: Referen e PICC diagram

Blo k A onsistsof two apa itors usedfor frequen y tuning.

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Blo k C onsistsof a Zenerdiodeused for powerregulation.

Blo k D is a urrent mirrorused forload modulation.

Blo kE isforload alibration. ChangingjumperJ1into a,b, anddpositiontheload

value ismodied.

At CON1 loadmodulationsignal isapplied.

With the voltage at CON2 the load an be adjusted until the required DC voltage is

shown at CON3.

In CON3 wemeasured the PICC DCvoltage with ahighimpedan evoltmeter.

CON4 is used for pi king up the PCD waveform parameters using a high impedan e

os illos ope probe.

In this work the ee ts of load modulation are not analyzed therefore the ir uit used for

simulation and measurements is a simplied version of this one and will be shown in further

se tions.

In1.2the omponent values areshown.

Table 1.2: Referen e PICC omponentslist

Component Value Component Value

L1 See AnnexD C1 7pF- 50pF(b)

L2 See AnnexD C2 3pF- 10pF(b)

R1

1.8kΩ

^C3 ^27pF

R2

0kΩ

^-

2kΩ

^(a) ^C4 ^1nF

R3

220Ω

^D1, ^D2,^D3, ^D4 ^BAR43S^or ^equivalent ^(
)

R4

51kΩ

^Dz ^BZX84, ^15V ^or ^equivalent ^(
)

R5

51Ω

^Q1a, ^Q1b ^BCV61A^or ^equivalent

R6

500kΩ

^Q2 ^BSS83^or ^equivalent

R7

110Ω

^D1, ^D2,^D3, ^D4 ACM3225-102-2P orequivalent

R8

51Ω

^CON1, ^CON2,^CON3, ^CON4 ^RF^onne
tor

R9

1.5kΩ

a: A multi-turn potentiometer (turns>10) shouldbeused

b: Q-fa tor shallbehigher than 100 at 13.56MHz

: Care should be taken on parameters Cj, Cp,Lsand Rsofequivalent diodes.

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Simulation and measurements

In this se tion the ir uit used for simulations will be introdu ed. It is simplied from the

Referen e PICC sin e it ex ludes the load modulation part. In addition, ADS simulations

results arepresented intime and frequen y domain. Inorder to analyze how the omponents

ae t the ir uit behavior, omponents with dierent values of basi parameters are used in

the simulations. Thebehaviorof the ir uit isinvestigated for thewide rangeof inputpower.

AlthoughthesimulationsareperformedusingADS, alltheresults areexportedtotheMatlab

domaininorder to makethe omparison withmeasurements easier.

Themethodfollowed tobuildthe ir uitinaPCBisalso reported. Afterward, thesetupused

isdes ribed and measurementsresults areshowed.

To on lude hapter two a omparison between simulation and measurement results is done

anddieren esare ommented.

2.1 Chip ard simulation

In this se tion one of the main goals of this work is overed: analyzing how some of the

omponentsae t the ir uit response, espe iallythe DC powermeasured intheload.

Ingure2.1the simulated ir uit isshown.

Figure 2.1: Simulated ir uit

Thevariable omponentsare

C

ⁱⁿ^,

C

^tp^and

R

^Lând^their^rangesâ

ording^to^the^listôn^standard

10373-6are:

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R L = 50Ω, 500Ω, 1kΩ, 1.5kΩ, 2kΩ

^(2.1)

C _in = 10pF, 27pF, 47pF

^(2.2)

C _tp = 470pF, 1nF

^(2.3)

The values were hosen onsidering real values of omponents sin e later on this ir uit was

builtand measurements were ompared withsimulation results. Spe ial arehave been taken

when hoosing the diode models sin e ADSallowsyou to set awide rangeof parameters that

annotbe easily foundin anormaldatasheet.

In thefollowing graphs 2.2 , 2.3 , 2.4 theinput power is swept from -2dBmto 20dBm. Three

dierentvaluesof

C

in ,

C

p

and

R

L

are hosen. The inputvoltageand input urrent ofthe hip

ardareplotted infrequen yandtime domain. The re tiedvoltageand theLissajous urves

arealsoplotted.

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1000 1050 1100 1150 1200

−3

−2

−1 0 1 2 3

ns

DUT voltage (V)

Simulated input voltage

−2dBm 5dBm 10dBm 15dBm 20dBm

−200 −150 −100 −50 0 50 100 150 200

−5 0 5 10 15 20 25 30 35

X: 15 Y: 24.11

frequency [MHz]

10 log 10 (DUTV freq )

Amplitude spectrum of input voltage

−2dBm 5dBm 10dBm 15dBm 20dBm

1000 1050 1100 1150 1200

−40

−30

−20

−10 0 10 20 30 40

ns

DUT current (mA)

Simulated input current

−2dBm 5dBm 10dBm 15dBm 20dBm

−200 −150 −100 −50 0 50 100 150 200

−35

−30

−25

−20

−15

−10

−5 0 5 10

X: 15 Y: 4.905

frequency [MHz]

10 log 10 (DUTC freq )

Amplitude spectrum of input current

−2dBm 5dBm 10dBm 15dBm 20dBm

−3 −2 −1 0 1 2 3

−40

−30

−20

−10 0 10 20 30 40

DUT current(mA)

DUT voltage (V) Lissajous curves

−2dBm 5dBm 10dBm 15dBm 20dBm

1000 0 1050 1100 1150 1200

0.2 0.4 0.6 0.8 1 1.2 1.4

ns

Rectified Voltage(V)

Simulated rectified voltage

−2dBm 5dBm 10dBm 15dBm 20dBm

Figure 2.2:

R

^L

= 50Ω

^,

C

ⁱⁿ ⁼^27pF,

C

^p ⁼^470pF

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1000 1050 1100 1150 1200

−5

−4

−3

−2

−1 0 1 2 3 4 5

ns

DUT voltage (V)

Simulated input voltage

−2dBm 5dBm 10dBm 15dBm 20dBm

−200 −150 −100 −50 0 50 100 150 200

−5 0 5 10 15 20 25 30 35

X: 15 Y: 26.73

frequency [MHz]

10 log 10 (DUTV freq )

Amplitude spectrum of input voltage

−2dBm 5dBm 10dBm 15dBm 20dBm

1000 1050 1100 1150 1200

−15

−10

−5 0 5 10 15

ns

DUT current (mA)

Simulated input current

−2dBm 5dBm 10dBm 15dBm 20dBm

−200 −150 −100 −50 0 50 100 150 200

−35

−30

−25

−20

−15

−10

−5 0 5

X: 15 Y: 1.429

frequency [MHz]

10 log 10 (DUTC freq )

Amplitude spectrum of input current

−2dBm 5dBm 10dBm 15dBm 20dBm

−5 0 5

−15

−10

−5 0 5 10 15

DUT current(mA)

DUT voltage (V) Lissajous curves

−2dBm 5dBm 10dBm 15dBm 20dBm

1000 0 1050 1100 1150 1200

0.5 1 1.5 2 2.5 3 3.5 4

ns

Rectified Voltage(V)

Simulated rectified voltage

−2dBm 5dBm 10dBm 15dBm 20dBm

Figure 2.3:

R

^L

= 1kΩ

^,

C

ⁱⁿ⁼^27pF,

C

^p ⁼^470pF

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1000 1050 1100 1150 1200

−6

−4

−2 0 2 4 6

ns

DUT voltage (V)

Simulated input voltage

−2dBm 5dBm 10dBm 15dBm 20dBm

−200 −150 −100 −50 0 50 100 150 200

−5 0 5 10 15 20 25 30 35

X: 15 Y: 26.97

frequency [MHz]

10 log 10 (DUTV freq )

Amplitude spectrum of input voltage

−2dBm 5dBm 10dBm 15dBm 20dBm

1000 1050 1100 1150 1200

−15

−10

−5 0 5 10 15

ns

DUT current (mA)

Simulated input current

−2dBm 5dBm 10dBm 15dBm 20dBm

−200 −150 −100 −50 0 50 100 150 200

−35

−30

−25

−20

−15

−10

−5 0 5

X: 15 Y: 1.081

frequency [MHz]

10 log 10 (DUTC freq )

Amplitude spectrum of input current

−2dBm 5dBm 10dBm 15dBm 20dBm

−6 −4 −2 0 2 4 6

−15

−10

−5 0 5 10 15

DUT current(mA)

DUT voltage (V) Lissajous curves

−2dBm 5dBm 10dBm 15dBm 20dBm

1000 0 1050 1100 1150 1200

0.5 1 1.5 2 2.5 3 3.5 4 4.5

ns

Rectified Voltage(V)

Simulated rectified voltage

−2dBm 5dBm 10dBm 15dBm 20dBm

Figure 2.4:

R

^L

= 2kΩ

^,

C

ⁱⁿ⁼^27pF,

C

^p ⁼^470pF

At rst sight, we noti e that the re tiedvoltage in reases when

R

L

and theinput power in-

reased. Whentheresistor

R

L

istoolowasin2.2itisnotpossibleto getastableDCvoltage.

FromtheLissajous urvesweobserve thatforlowinputpowertheshape isaellipse butwhen

wein reasetheinputpowertheellipsesstartto hangetheirshapebe auseofnonlinearee ts

inthere tier [6℄ [7 ℄.

At this pointwe willstart analyzing howthe dierent omponentsmentioned before

R

L ,

C

in

,

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C

^p înuen
e^the înput ^voltage ôr ^the ^DC^voltage¹ ôf ^theîr
uit.

Inthefollowing graphsaninput power of 20dBmisapplied. Thevalueof

R

L

issweptand

thevaluesofthe apa itorsaremodiedinea hgraphtoshowhowitae tstheinputvoltage,

input urrent and Lissajous urves plotted.

1000 1050 1100 1150 1200

−6

−4

−2 0 2 4 6

Input voltage Cin = 47pF, Cp = 470pF

ns

PICC input voltage

R1 = 2kΩ R2 = 1.5kΩ R3 = 1kΩ R4 = 500Ω R5 = 50Ω

1000 1050 1100 1150 1200

−6

−4

−2 0 2 4 6

Input voltage Cin = 10pF, Cp = 1nF

ns

PICC input voltage

R1 = 2kΩ R2 = 1.5kΩ R3 = 1kΩ R4 = 500Ω R5 = 50Ω

Figure 2.5: DUTinput voltage

1000 1050 1100 1150 1200

−40

−30

−20

−10 0 10 20 30 40

Input current Cin = 47pF, Cp = 470pF

ns

PICC input current

R1 = 2kΩ R2 = 1.5kΩ R3 = 1kΩ R4 = 500Ω R5 = 50Ω

1000 1050 1100 1150 1200

−40

−30

−20

−10 0 10 20 30 40

Input current Cin = 10pF, Cp = 1nF

ns

PICC input current

R1 = 2kΩ R2 = 1.5kΩ R3 = 1kΩ R4 = 500Ω R5 = 50Ω

Figure 2.6: DUT Current

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−6 −4 −2 0 2 4 6

−40

−30

−20

−10 0 10 20 30 40

DUT voltage (V)

DUT current (mA)

Lissajous curves Cin = 47pF,Cp = 470pF

R1 = 2kΩ R2 = 1.5kΩ R3 = 1kΩ R4 = 500Ω R5 = 50Ω

−6 −4 −2 0 2 4 6

−40

−30

−20

−10 0 10 20 30 40

DUT voltage (V)

DUT current (mA)

Lissajous curves Cin = 10pF,Cp = 1nF

R1 = 2kΩ R2 = 1.5kΩ R3 = 1kΩ R4 = 500Ω R5 = 50Ω

Figure 2.7: Lissajous urves

From the graphs we noti e that there is almost no hange on the input voltage when apa -

itan es

C

p

and

C

in

are hanged but when in reasing

R

L

the input voltage of the hip also

in reases.

Inthegraphs below the value of

R

L

and

C

p

are xedand againan input power of 20dBm

isapplied. Wewill evaluate theee tsof

C

ⁱⁿ ôn^the înput^voltage ând ûrrent.

1000 1050 1100 1150 1200

−5

−4

−3

−2

−1 0 1 2 3 4 5

PICC input voltage (V)

ns

Input voltage R = 500Ω , Cp = 470pF

C1 = 10pF C2 = 27pF C3 = 47pF

1000 1050 1100 1150 1200

−5

−4

−3

−2

−1 0 1 2 3 4 5

PICC input voltage (V)

ns

Input voltage R = 1kΩ , Cp = 1nF

C1 = 10pF C2 = 27pF C3 = 47pF

Figure 2.8: DUTinput voltage

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1000 1050 1100 1150 1200

−25

−20

−15

−10

−5 0 5 10 15 20 25

PICC input current (V)

ns

Input current R = 500Ω , Cp = 470pF

C1 = 10pF C2 = 27pF C3 = 47pF

1000 1050 1100 1150 1200

−25

−20

−15

−10

−5 0 5 10 15 20 25

PICC input current (mA)

ns

Input current R = 1kΩ , Cp = 1nF

C1 = 10pF C2 = 27pF C3 = 47pF

Figure 2.9: DUT Current

−5 0 5

−25

−20

−15

−10

−5 0 5 10 15 20 25

DUT current (mA)

DUT voltage (V) Lissajous curves R = 500Ω , Cp = 470pF

C1 = 10pF C2 = 27pF C3 = 47pF

−5 0 5

−25

−20

−15

−10

−5 0 5 10 15 20 25

DUT current (mA)

DUT voltage (V) Lissajous curves R = 1kΩ , Cp = 1nF

C1 = 10pF C2 = 27pF C3 = 47pF

Whentheinput apa itan e

C

ⁱⁿîs^smaller^theînput^voltage^slightlyîn
reasesând^the^Lissajous

urvesbe ome narroweron the yaxis.

Now we will analyze the ee t of thethird element

C

^p ôn ^the înput^voltage ând ûrrent.

R

^L

and

C

in

arexedand aninput power of 20dBmisapplied.

(21)

1000 1050 1100 1150 1200

−3

−2

−1 0 1 2 3

PICC input voltage (V)

ns

Input voltage R = 50Ω , Cin = 47pF

C1 = 1nF C2 = 470pF

1000 1050 1100 1150 1200

−6

−4

−2 0 2 4 6

PICC input voltage (V)

ns

Input voltage R = 1.5kΩ , Cin = 10pF C1 = 1nF C2 = 470pF

Figure 2.11:DUT input voltage

1000 1050 1100 1150 1200

−40

−30

−20

−10 0 10 20 30 40

PICC input current (mA)

ns

Input current R = 50Ω , Cin = 47pF

C1 = 1nF C2 = 470pF

1000 1050 1100 1150 1200

−15

−10

−5 0 5 10 15

PICC input current (mA)

ns

Input current R = 1.5kΩ , Cin = 10pF

C1 = 1nF C2 = 470pF

Figure 2.12:DUT Current

−3 −2 −1 0 1 2 3

−40

−30

−20

−10 0 10 20 30 40

DUT current (mA)

DUT voltage (V) Lissajous curves R = 50Ω , Cin = 47pF

C1 = 1nF C2 = 470pF

−6 −4 −2 0 2 4 6

−15

−10

−5 0 5 10 15

DUT current (mA)

DUT voltage (V) Lissajous curves R = 1.5kΩ , Cin = 10pF

C1 = 1nF C2 = 470pF

The input urrent aswell asthe input voltage areslightly modied by

C

^p ^when ^the^value ^of

theresistorin rease.

(22)

1000 1050 1100 1150 1200 0.5

1 1.5 2 2.5 3 3.5 4 4.5

ns

Retified voltage

Rectified voltage Cin = 10pF,Cp = 470pF R1 = 2kΩ R2 = 1.5kΩ R3 = 1kΩ R4 = 500Ω R5 = 50Ω

1000 1050 1100 1150 1200

0.5 1 1.5 2 2.5 3 3.5 4 4.5

ns

Retified voltage

Rectified voltage Cin = 27pF,Cp = 1nF R1 = 2kΩ R2 = 1.5kΩ R3 = 1kΩ R4 = 500Ω R5 = 50Ω

Figure 2.14: Re tied voltage

From the graphs we observe mutual dependen ebetween

C _p

^and

R _L

^. ^If ^the apa itan e is to highandresistan eistolow,thereislargevariationinthere tiedvoltage. Thisisundesirable

sin efor the hip's internal ir uit we need DCvoltage.

To on lude the simulation results se tion and with the aim of showing learly how

C

in and

C

^p âe
t ^the^re
tied^voltage,^two ^more^graphs âre^plotted. În^the^rstône

C

ⁱⁿ ^and^the^input

poweraresweptwhile

R

L

and

C

p

arexed andinthese ondone

C

p

andtheinputpowerare

sweptwhile

R

L

and

C

in

aremodied.

1000 0 1050 1100 1150 1200

0.5 1 1.5 2 2.5 3 3.5 4 4.5

ns

Retified voltage

Rectified voltage R = 1kΩ, Cin = 10pF

C1 = 1nF C2 = 470pF

1000 0 1050 1100 1150 1200

0.5 1 1.5 2 2.5 3 3.5 4

ns

Retified voltage

Rectified voltage R = 1kΩ , Cp = 1nF

C1 = 10pF C2 = 27pF C3 = 47pF

Figure 2.15: Re tied voltage modifying

C

in

(right) and

C

p (left)

Asitisvisibleinthegraphswe have5 groupsoflinesandgoingfromtopto bottom theupper

groupoflines orrespondto a inputpowerof 20dBm,thefollowing to 15dBm andsoon.

Analyzingthose imagesiftheinputpowerislow thereisno appre iabledieren e when

C

p is

(23)

In this se tion the pro edure followed to design and build the simulated ir uit is des ribed.

Afterward,thesetupusedisintrodu edandthemeasurementresults areshownasitwasdone

forsimulation.

2.2.1 PICC design and onstru tion

ThesimulatedPICC ir uitwasbuiltinaPCBboard. Firstofall,the ir uitwasdesignedus-

ingEaglePCB designsoftware. Surfa eMountedDevi es(SMD)andnormal size omponents

were used. In the layout two layers of opper were used, one ea h side of the board. Figure

2.16shows thelayout.

Figure 2.16: Cir uitlayout

On ethedesign was ready, itwasprintedusing alaserprinteron a photopositive lm paper

togetthe mask. Figure2.17 showsthe top and bottomlayerofthemask.

Figure 2.17:Mask front andba k

(24)

entire surfa e of the substratewasrstplated, and later ontheareas thatare not partofthe

desiredpattern weresubtra ted.

Afterthe maskwasmade, itwaspla ed onto the photo-sensitive PCBboard andwasexposed

totheUVfor30se . Thenextstepwasthedeveloping pro ess. Herethesensitizedphotoresist

wastakenawayusingadeveloperinordertounprote tthe oopertoremove. Thentheet hing

pro ess was performedto remove the ooperleft.

At thattimethe board was leaned withal ohol and running water.

To end thebuilding pro ess of the PCB a manual driller was used to make theholes for the

omponentsand onne tionsof the PCB.Inthe nalstep allthe omponents where soldered.

Figure2.18shows the PICC ir uitbuilt.

Figure 2.18:PICC built

Theparts ofthe ir uithavebeenlabeledinthepi tureandtheywillbedes ribedinthenext

paragraphs. Numberslabelthe omponentsand letters thepinsusedfor measurements.

1: A SMA onne tor was used to onne t the signal generatorto thePCB. The power

values usedwere -2dBm,5dBm,10dBm, 15dBm and20dBm..

2: Thisresistor is a

50Ω

^resistorîn
luded ⁱⁿ^the ^setup ^for ^measuring ^theînput ûrrent

sin e there werenot urrent probesavailable for thats ope.

(25)

5 and 6: There are two

0Ω

^resistors ⁱⁿ ^series ^with

R

^L ^and ^the

50Ω

^resistor ^able ^to ^be

desoldered ifneeded.

7: A

50Ω

^resistor ^was âlso în
luded ^right âfter

R

L

to ensure that the load resistor is

never0.

8 and9: Twojumpersareusedto hangethevalueoftheinputandparallel apa itan e.

For theloadresistor

R

^L ^apotentiometer

(0 − 2kΩ)

^is ^used.

A and B: Those pins are used to measure the input urrent of the hip using two

hannels ofthes ope. Theinputvoltage ofthePICC isdire tlymeasuredinpinB,just

right afterthe resistor.

Cand D:Formeasuring there tiedvoltageweuseagaintwo hannelofthes opeand

subtra t themusing those pins.

E: Ground ofthe ir uit.

Inorderto omparethesimulationswiththemeasurementstheinputvoltage,input urrentand

re tiedvoltageofthe Devi eundertest(DUT) shallbemeasured. Thesignalgeneratorused

wasRohdeS hwarzSMF100A[8℄[9℄andtheos illos opewasadigitalstorageos illos opeDSO-

X3024Afrom Agilent Te hnologies. Thesame devi es where usedfor all themeasurements.

2.2.2 Setup and results

Figure2.19shows the setupused. Alter waspla edbetween theDUT and thesignal gener-

atorinorderto an el out the harmoni s ofthegenerator. Thislter isdes ribedin[6 ℄.

Figure 2.19: Measurement setup

(26)

areshown. The variableelementsand the rangewas the sameasinsimulation 2.1,2.2 , 2.3 .

−100 −50 0 50 100

−2.5

−2

−1.5

−1

−0.5 0 0.5 1 1.5 2 2.5

ns

DUT voltage (V)

Measured input voltage

−2dBm 5dBm 10dBm 15dBm 20dBm

−200 −150 −100 −50 0 50 100 150 200

−5 0 5 10 15 20 25 30 35 40

X: 12.52 Y: 28.5

frequency [MHz]

10 log 10 (DUTV freq )

Amplitude spectrum of measured input voltage

−2dBm 5dBm 10dBm 15dBm 20dBm

−100 −50 0 50 100

−30

−20

−10 0 10 20 30

ns

DUT Current (mA)

Measured input current

−2dBm 5dBm 10dBm 15dBm 20dBm

−200 −150 −100 −50 0 50 100 150 200

−35

−30

−25

−20

−15

−10

−5 0 5 10 15

X: 12.52 Y: 8.648

frequency [MHz]

10 log 10 (DUTC freq )

Amplitude spectrum of measured input current

−2dBm 5dBm 10dBm 15dBm 20dBm

−2.5 −2 −1.5 −1 −0.5 0 0.5 1 1.5 2 2.5

−30

−20

−10 0 10 20 30

DUT current(mA)

DUT voltage (V) Lissajous curves

−2dBm 5dBm 10dBm 15dBm 20dBm

−100 −50 0 50 100

−0.1 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9

ns

Rectified voltage (V)

Measured rectified voltage

−2dBm 5dBm 10dBm 15dBm 20dBm

Figure 2.20:

R

L

= 50Ω

^,

C

in

= 27pF,

C

p

=470pF

(27)

−100 −50 0 50 100

−4

−3

−2

−1 0 1 2 3 4

ns

DUT voltage (V)

Measured input voltage

−2dBm 5dBm 10dBm 15dBm 20dBm

−200 −150 −100 −50 0 50 100 150 200

−5 0 5 10 15 20 25 30 35 40

X: 12.52 Y: 30.43

frequency [MHz]

10 log 10 (DUTV freq )

Amplitude spectrum of measured input voltage

−2dBm 5dBm 10dBm 15dBm 20dBm

−100 −50 0 50 100

−20

−15

−10

−5 0 5 10 15 20

ns

DUT Current (mA)

Measured input current

−2dBm 5dBm 10dBm 15dBm 20dBm

−200 −150 −100 −50 0 50 100 150 200

−35

−30

−25

−20

−15

−10

−5 0 5 10 15

X: 12.52 Y: 6.657

frequency [MHz]

10 log 10 (DUTC freq )

Amplitude spectrum of measured input current

−2dBm 5dBm 10dBm 15dBm 20dBm

−4 −3 −2 −1 0 1 2 3 4

−20

−15

−10

−5 0 5 10 15 20

DUT current(mA)

DUT voltage (V) Lissajous curves

−2dBm 5dBm 10dBm 15dBm 20dBm

−100 0 −50 0 50 100

0.5 1 1.5 2 2.5 3 3.5

ns

Rectified voltage (V)

Measured rectified voltage

−2dBm 5dBm 10dBm 15dBm 20dBm

Figure 2.21:

R

L

= 1kΩ

^,

C

in

=27pF,

C

p

=470pF

(28)

−100 −50 0 50 100

−5

−4

−3

−2

−1 0 1 2 3 4 5

ns

DUT voltage (V)

Measured input voltage

−2dBm 5dBm 10dBm 15dBm 20dBm

−200 −150 −100 −50 0 50 100 150 200

−5 0 5 10 15 20 25 30 35 40

X: 12.52 Y: 30.79

frequency [MHz]

10 log 10 (DUTV freq )

Amplitude spectrum of measured signal

−2dBm 5dBm 10dBm 15dBm 20dBm

−100 −50 0 50 100

−20

−15

−10

−5 0 5 10 15 20

ns

DUT Current (mA)

Measured input current

−2dBm 5dBm 10dBm 15dBm 20dBm

−200 −150 −100 −50 0 50 100 150 200

−5 0 5 10 15 20 25 30 35 40

X: 12.52 Y: 30.79

frequency [MHz]

10 log 10 (DUTV freq )

Amplitude spectrum of measured input voltage

−2dBm 5dBm 10dBm 15dBm 20dBm

−5 0 5

−20

−15

−10

−5 0 5 10 15 20

DUT current(mA)

DUT voltage (V) Lissajous curves

−2dBm 5dBm 10dBm 15dBm 20dBm

−100 0 −50 0 50 100

0.5 1 1.5 2 2.5 3 3.5 4

ns

Rectified voltage (V)

Measured rectified voltage

−2dBm 5dBm 10dBm 15dBm 20dBm

Figure 2.22:

R

^L

= 2kΩ

^,

C

ⁱⁿ ⁼^27pF,

C

^p ⁼^470pF

A lear dieren e fromthesimulation graphsis noti eable: thegraphsof there tied voltage

andtheinput urrent looka noisier now.

Asitwassaidbefore, therewerenotdierential probesavailablefor theos illos ope usedand

thosemeasures amefromsubtra tingtwo hannels onthes opewhi hresultsinanin rement

ofthenoise.

(29)

−100 −50 0 50 100

−1

−0.5 0 0.5 1 1.5 2 2.5 3 3.5

ns

Retified voltage (V)

Rectified voltage Cin = 47pF,Cp = 470pF R1 = 2kΩ R2 = 1.5kΩ R3 = 1kΩ R4 = 500Ω R5 = 50Ω

−100 −50 0 50 100

−1

−0.5 0 0.5 1 1.5 2 2.5 3 3.5 4

ns

Retified voltage (V)

Rectified voltage Cin = 10pF,Cp = 1nF R1 = 2kΩ R2 = 1.5kΩ R3 = 1kΩ R4 = 500Ω R5 = 50Ω

Figure 2.23: Re tied voltage

Similar ee tstosimulation areobserved. There isadependen e between

C p

^and

R L

^and^the

DCvoltage be ame morestablewhen in reasing

R _L

^.

To end this se tion the re tied voltage will be also plotted xing the resistan e

R

L

and one

ofthe apa itors (

C

p or

C

in

) and makinga sweep on theinputpower.

−100 0 −50 0 50 100

0.5 1 1.5 2 2.5 3 3.5

Rectified voltage R = 1kΩ, Cin = 10pF

ns

Retified voltage

C1 = 1nF C2 = 470pF

−100 0 −50 0 50 100

0.5 1 1.5 2 2.5 3 3.5

ns

Retified voltage

Rectified voltage R = 1kΩ , Cp = 1nF

C1 = 10pF C2 = 27pF C3 = 47pF

Figure 2.24: Re tied voltage modifying

C

ⁱⁿ ^(right) ^and

C

^p ^(left)

Fromtoptobottomtheinputpowerisde reased,sotheuppergroupofthreelines orrespond

to thehigher input power(20dBm).

Althoughherethe ee ts annotbe learly noti edinse tion2.3this problemwillbesolved.

2.3 Analyzing simulation and measurements results

Inpreviousse tionsofthis haptersimulation andmeasurement resultsarepresentedindepen-

dently. NowI have tried to nda ommon tenden yfor the ir uit behavior.

In the following graphs two values are xed and one is swept. A power sweep was also per-

formed. The graphs are presented as the input/re tied voltage versus input power and the

resultsprodu ed are ommented.

(30)

with there tiedvoltage.

At that point simulation and measurement results for theinput voltage are ompared inthe

samegraph. Thevaluesofthetwoinvariable omponentsarewrittenasthetitleofthegraphs.

In the rst pair of graphs

R

in

is swept, in the se ond

C

in

is swept and in thethird on

C

p is

swept.

Thepower sweep is showninthex-axis.

Simulation results are presented in dashed line and measurement results are shown in solid

line.

−5 0 5 10 15 20

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5

Cin = 10pF, Cp = 470pF

Input voltage (V)

Input power (dBm) R1 = 2kΩ

R2 = 1.5kΩ R3 = 1kΩ R4 = 500Ω R5 = 50Ω

−5 0 5 10 15 20

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5

Cin = 27pF, Cp = 1nF

Input voltage (V)

Input power (dBm) R1 = 2kΩ

R2 = 1.5kΩ R3 = 1kΩ R4 = 500Ω R5 = 50Ω

Figure 2.25: Input voltage simulatedand measured,

R

L sweep

−5 0 0 5 10 15 20

0.5 1 1.5 2 2.5 3 3.5 4

Cp = 470pF, R = 1kΩ

Input voltage (V)

Input power (dBm) C1 = 10pF

C2 = 10pF C3 = 27pF C1 = 27pF C2 = 47pF C3 = 47pF

−5 0 5 10 15 20

0 0.5 1 1.5 2 2.5 3 3.5 4

Cp = 1nF, R = 1kΩ

Input voltage (V)

Input power (dBm) C1 = 10pF

C2 = 10pF C3 = 27pF C1 = 27pF C2 = 47pF C3 = 47pF

Figure 2.26: Input voltage simulatedand measured,

C

ⁱⁿ^sweep

(31)

−5 0 5 10 15 20 0

0.5 1 1.5 2 2.5 3 3.5 4

Cin = 10pF, R = 1kΩ

Input voltage (V)

Input power (dBm) C1 = 1nF

C2 = 1nF C3 = 470pF C4 = 470pF

−5 0 5 10 15 20

0 0.5 1 1.5 2 2.5 3 3.5 4

Cin = 47pF, R = 1k Ω

Input voltage (V)

Input power (dBm) C1 = 1nF

C2 = 1nF C3 = 470pF C4 = 470pF

Figure 2.27: Inputvoltage simulated and measured,

C

p sweep

Asimilarbehaviorbetween measuredandsimulatedinputvoltage isillustratedonthegraphs.

Modifying

C

p

slightlyae tstheinputvoltagehoweverin reasing

C

in

redu estheinputvoltage.

A good measure to ompare the simulation with the measurement results when the signal

is losed to a sine wave is omparing the dieren e of the harmoni s. As an example, for

NXP a dieren e of 10dBis understoodas agood alignment between thesimulation andthe

measurement. Consequently an spe tral analysis is performed for measured and simulated

inputvoltage and input urrent in 2.28 ,2.29 , 2.30 and2.31 .

(32)

−200 −150 −100 −50 0 50 100 150 200

−5 0 5 10 15 20 25 30 35 40

X: 12.52 Y: 30.54

frequency [MHz]

10 log 10 (DUTV freq )

Measurement

−2dBm 5dBm 10dBm 15dBm 20dBm

−200 −150 −100 −50 0 50 100 150 200

−5 0 5 10 15 20 25 30 35

X: 15 Y: 26.89

frequency [MHz]

10 log 10 (DUTV freq )

Simulation

−2dBm 5dBm 10dBm 15dBm 20dBm

Figure 2.28:FFT inputvoltage,

R

^L

= 1.5kΩ

^,

C

ⁱⁿ

= 27pF

^,

C

^p

= 470pF

−200 −150 −100 −50 0 50 100 150 200

−5 0 5 10 15 20 25 30 35 40

X: 13.01 Y: 35.89

frequency [MHz]

10 log 10 (DUTV freq )

Measurement

−2dBm 5dBm 10dBm 15dBm 20dBm

−200 −150 −100 −50 0 50 100 150 200

−5 0 5 10 15 20 25 30 35

X: 15 Y: 26.47

frequency [MHz]

10 log 10 (DUTV freq )

Simulation

−2dBm 5dBm 10dBm 15dBm 20dBm

Figure 2.29:FFT inputvoltage,

R

^L

= 500Ω

^,

C

ⁱⁿ

= 10pF

^,

C

^p

= 1nF

(33)

−200 −150 −100 −50 0 50 100 150 200

−25

−20

−15

−10

−5 0 5 10 15

X: 12.52 Y: 6.693

frequency [MHz]

10 log 10 (DUTC freq )

Measurement

−2dBm 5dBm 10dBm 15dBm 20dBm

−200 −150 −100 −50 0 50 100 150 200

−35

−30

−25

−20

−15

−10

−5 0 5

X: 15 Y: 1.19

frequency [MHz]

10 log 10 (DUTC freq )

Simulation

−2dBm 5dBm 10dBm 15dBm 20dBm

Figure 2.30: FFTinput urrent,

R

^L

= 1.5kΩ

^,

C

ⁱⁿ

= 27pF

^,

C

^p

= 470pF

−200 −150 −100 −50 0 50 100 150 200

−25

−20

−15

−10

−5 0 5 10 15

X: 13.01 Y: 11.19

frequency [MHz]

10 log 10 (DUTC freq )

Measurement

−2dBm 5dBm 10dBm 15dBm 20dBm

−200 −150 −100 −50 0 50 100 150 200

−35

−30

−25

−20

−15

−10

−5 0 5

X: 15 Y: 0.8478

frequency [MHz]

10 log 10 (DUTC freq )

Simulation

−2dBm 5dBm 10dBm 15dBm 20dBm

Figure 2.31: FFTinput urrent,

R

^L

= 500Ω

^,

C

ⁱⁿ

= 10pF

^,

C

^p

= 1nF

Two dierent setof valueswere hosen to perform thefrequen y analysis.

A ursorispla edontheplottedgraphssothemaximumvalueislabeledand anbe ompared.

Forbothpairsofgraphsthedieren ebetweentheamplitudeofthespe trumislessthan10dB

sowe an assumea goodmat hing withinsimulation andmeasurement.

Fromthegraphsit an alsobeobservedthatwhentheinputpowerisin reasedtheharmoni s

alsoin reased.

At thatpoint we will startanalyzing theresults for there tiedvoltage.

Asit was done previously, simulation and measurement results for re tied voltage are om-

paredinthesame graph.

Simulation results are presented in dashed line and measurement results are shown in solid

line.

(34)

−5 0 0 5 10 15 20 0.5

1 1.5 2 2.5 3 3.5 4 4.5

Cin = 10pF, Cp = 470pF

Rectified voltage (V)

Input power (dBm) R1 = 1.5kΩ

R2 = 1.5kΩ R3 = 1kΩ R4 = 1kΩ R5 = 2kΩ R1 = 2kΩ R2 = 50Ω R3 = 50Ω R4 = 500Ω R5 = 500Ω

−5 0 5 10 15 20

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5

Cin = 27pF, Cp = 1nF

Rectified voltage (V)

Input power (dBm) R1 = 1.5kΩ

R2 = 1.5kΩ R3 = 1kΩ R4 = 1kΩ R5 = 2kΩ R1 = 2kΩ R2 = 50Ω R3 = 50Ω R4 = 500Ω R5 = 500Ω

Figure 2.32: Re tied voltage simulated and measured,

R

L sweep

−5 0 5 10 15 20

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5

Cp = 470pF, R = 2kΩ

Rectified voltage (V)

Input power (dBm) C1 = 10pF

C2 = 10pF C3 = 27pF C1 = 27pF C2 = 47pF C3 = 47pF

−5 0 5 10 15 20

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5

Cp = 1nF, R = 2kΩ

Rectified voltage (V)

Input power (dBm) C1 = 10pF

C2 = 10pF C3 = 27pF C1 = 27pF C2 = 47pF C3 = 47pF

Figure 2.33:Re tied voltage simulated and measured,

C

in sweep

−5 0 0 5 10 15 20

0.5 1 1.5 2 2.5 3 3.5 4

Cin = 10pF, R = 2k Ω

Rectified voltage (V)

Input power (dBm) C1 = 1nF

C2 = 1nF C3 = 470pF C4 = 470pF

−5 0 5 10 15 20

0 0.5 1 1.5 2 2.5 3 3.5 4

Cin = 47pF, R = 2k Ω

Rectified voltage (V)

Input power (dBm) C1 = 1nF

C2 = 1nF C3 = 470pF C4 = 470pF

C

(35)

the resistor

R

L

value are in reased. The more resistan e you have, the slower the apa itor

andis hargetherefore ahigher voltage isobtained.

If we look at ea h pair of graphs we an noti e that when the parallel apa itan e hanges

andtheinput apa itan e doesnot there isaslightly dieren e onthere tiedvoltage, being

somehow higher whentheparallel apa itan eis larger.

Ontheotherhand ifwe varytheinput apa itan e

C

in

butleave

C

p

onstantand theresistor

R

^L ^is^up ^to

500Ω

^,^we ^eviden
e ^that^the ^re
tied^voltage ^de
reases ^when

C

ⁱⁿ ^in
reases.

To end this se tion, the remarkable ee ts on the voltages produ ed be ause of thevariation

ofthe omponents willbe summarized.

Consequen eson inputand re tiedvoltage aresimilar:

In reasing

R

L

and the inputpowerprodu esa higherinput and re tiedvoltage.

In reasing

C

in

de reases the inputand re tiedvoltage.

Apparently there are no signi ant hanges on the input and re tied voltage when

C

^p

is modied, ex eptthatthere tied voltage be ame more stablewhen

C

p

isin reased.

(36)

Test PCD assembly

3.1 Des ription

Chapterthreein ludes theTest PCDassemblymeasurements.

Thetest apparatus isdened indetailinISO/IEC 10373-6 [5 ℄and ECMA-356[10℄.

The primary purpose of this test assembly is to measure the load modulation oe ients of

onta tless ards,tagsor devi es dependent on the eldstrength. Thistest setupis alsoused

asa standard reader antenna for other testsand measurements on ards (PICC), like testing

the inuen eof the reader's signalwaveform andthe ard'sabilityto dete t them orre tly.

Parts oftest PCD assembly areexplainedand pi tures showthesetupused.

ThePCDantennaisshowed ingure3.1. Itisaoneturn oilof150mmdiameter. It ontains

animpedan emat hingnetwork.

(37)

one oil is in opposite phase to theother. The goal ofthese oilsit to measurethe magneti

eldstrengthat a ertaindistan efrom thereader.

The alibration oil is xedto one ofthesense oils. Ontheother oil, thePICC ardis set.

The alibration oil onsists of a printed ir uit board whi h has the height and width of an

ID-1 type dened in ISO/7810 ontaining a single turn oil on entri with the ard outline

[11 ℄.

The alibration fa tor isgiven by thegeometry of the oil and is 900mV (peak-to-peak) for a

magneti eldstrength ofa 1.0A/m(rms) at the operatingfrequen y of 13.56MHz.

The magneti eld strength an be al ulated from the measured voltage on the alibration

oilbythefollowing formula:

H RM S = 3.11 ∗ V RM S

^(3.1)

Figure 3.2: Sense oil and alibration oil

ThePICC ardisshowningure3.3. Thepartsand omponentsofthereferen ePICC where

des ribed in1.2 . It isa lass1 ard alsoprovided byNXP.

(38)

Thereisalsoabalan ing ir uit onsistingofa

10Ω

potentiometer andtwo

240Ω

^resistors^used

to adjustthebalan e point when the sense oils arenot loadedbyaPICC.

Figure 3.4: Compensation ir uit

Figure3.5givesan overview ofthetest PCDassembly.

Theantennaispla ed inthemiddleandthe distan efromthe oilsto theantennaisthesame

andequal to37.5 mm. The alibration oil isxedtothe downer sense oil andtheDUT will

be pla einto the uppersense oil. Thebalan ing ir uit is ontheright side of thegure.

(39)

3.2 Referen e PICC test using a reader emulator

Before any test of PCD wasperformed theresonan e frequen y of the ardshould be known

andthebalan ing ir uit of PCDtest assembly shouldbe tested.

With the alibration oil in pla e but without the DUT ard in position the signal on the

probe onne tedtothebalan ing ir uitshouldbebelow20mV(peakto peak)whentheinput

power is in reased until the probe on the alibration oil measures 2V (peak to peak). The

10Ω

poten iometerP1 an be adjustfor a minimum outputvoltage [11 ℄.

Therearedierentmethodsofmeasuring theresonan efrequen yofthe hip ard[12℄[13 ℄[14 ℄.

Inthiswork,aVe tornetworkanalyzer(VNA)wasusedandtheS11 parameterwasmeasured

[15 ℄.

Firstlythe alibration kit wasusedto alibrate one-port ofVNA. Theresonan efrequen y of

a lass1 PICC andan ePassletSuite wasmeasuredusing thesetup in3.6.

(40)

Later on, the VNA was alibrated using the alibration oil in gure 3.6 as short instead of

theshorton the alibrationkit.

Thedimensionsofthe oilarer=13mm,w=0.5mm,g =0.7mmandN =6. Withthesame

setupthe resonan efrequen y wasmeasured again.

Results of the resonan e frequen y measurement using the normal alibration or the ustom

alibrationare shownin gures 3.7and 3.8 for the lass1 PICC and theePasslet Suite. The

normal alibrationisplotted on theleft sideand the ustom alibrationon theright side.

(41)

In thegures where the normal alibration wasused it is noti eable a mismat h in theright

sideof the graphbut whenusing the ustom alibrationthis mismat h disappears.

When the resonan e frequen y of the lass 1 PICC was measured and he ked that it was

around16.5MHzthe following test pro edurewas done.

1: The PICC waspla ed into the DUTpositionon theTest PCDassembly.

2: A sine wave with a magneti eld strength of 1.5A/m, 3A/m, 4.5A/m and 7.5A/m

wasapplied.

3: Thevoltageonthe alibration oilwasmeasuredtoverifytheoperatingmagneti eld

strength.

4: ThejumperJ1 wasswit htoposition'b'andR2wasadjustedto obtainaDCvoltage

of 3V or 6Vmeasured at CON3.

The dierent values ofR2 werenoted.

(42)

Figure 3.10:Testsetup

(43)

H RM S

^1.5A/m ³ ^A/m ^4.5A/m ^7.5A/m

V _{RM S}

^0.4812^V ^0.9642 ^V ^1.4464 ^V ^2.4106^V

Table 3.1:

V RM S

^for ^dierent ^magneti^eld ^strength

The values of the variable resistor R2 measured for the dierent magneti eld strength are

showninthefollowing graph.

Asanexample,gure3.12showsas reenshotfromthes opewherethebluesignalisthesignal

measured in the balan ing ir uit, the green signal is thesignal measured on the alibration

oil(in this ase, orresponding to amagneti eldstrengthof 7.5A/m)and theyellowsignal

intheDC voltage measured inCON3,inthis asearound 3V.

1 2 3 4 5 6 7 8

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2

R2 (k Ω )

Hrms (A/m) R2

3V CON3 6V CON3

Figure 3.11: R2values for dierent magneti eldstrength

(44)

Ifthe magneti eldstrength is in reased a smallervalue of R2 isneeded to obtain the same

DCvoltage measured inCON3.

Later on, the jumper J1 was swit hed to position ' ' and an external sour e of voltage was

onne tedinCON2asshown in3.13. Nowthe loadof thePICC ismodiedusing CON2and

theDCvoltage is measuredat CON3.

The voltage in CON2 is modied until the desired voltage of 3V or 6V is rea hed in CON3.

Thedierent values oftheadding voltage andnoted.

(45)

Thenext gureshows themeasurementsdone.

1 2 3 4 5 6 7 8

0 0.5 1 1.5 2 2.5 3 3.5

CON2 (V)

Hrms (A/m) Voltage at CON2

3V CON3 6V CON3

Figure 3.14: CON2values for dierent magneti eldstrength

(46)

inorderto getthe same voltage (3Vor 6V)at CON3.

(47)

Con lusion and Outlook

Thisthesis overs the analysisof non linear behavior of lass 1 PICCs a ordingto standard

ISO14443. Ithasbeen shownhowthevariationofsome omponentsae tstheinputvoltage,

input urrent and DC voltage ofthe ard.

Inthereferen e ir uitusedformeasurementsDC-outputvoltagesofthere tierdonothavea

referen etoground. Theyarepulsatingin ommon modewith13.56MHz. Inorderto improve

themeasurements, a tivedierentialprobes ouldbe usedinfurthertimestomeasuretheDC

voltage and the input urrent of theDUT. Withthese probes results should have best noise

performan e and the least parasiti apa itan e. It wasalso noti eable from theFastFourier

Transform(FFT)analysisthat the harmoni s growwhen theinput power is in reased.

It wasmention in thebeginning that theloadmodulation wouldn't be in luded inthis work.

AfterhavinganalyzedthepowersupplyofthePICCthenextlogi alstepwouldbetointrodu e

insimulationaswellasinmeasurementsthe omponents orrespondingtotheloadmodulation

andanalyze howthe ard ommuni ates withthereader.

Onthe other side, a test using the PCD assembly wasperformed in3.2 . To make sure what

ouldwe expe tfrom this emulator and also ontinue thetra kof this work omparing simu-

lationand measurement,itwouldbe agood ideato simulatedthePCD assemblyinADSand

ompare it withthe measurement results. For this purpose, the oupling fa tor between the

PICC oil and the PCD oilshould be known andthelosses dueto themeasurement devi es,

su hasampliersand attenuators, should be onsidered.

Asthe load modulation was not in luded only PICC testsdened in ISO 10373-6 have been

a omplishedalthoughtheee tsofloadmodulation shouldbealsoin luded infutureworks.

(48)

1.1 Operatingprin iple onta tless hip ards . . . 2

1.2 Communi ationinterfa e diagram . . . 4

1.3 Referen e PICC diagram . . . 4

2.1 Simulated ir uit . . . 6

2.2

R

^L

= 50Ω

^,

C

ⁱⁿ ⁼^27pF,

C

^p ⁼^470pF ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ⁸

2.3

R

^L

= 1kΩ

^,

C

ⁱⁿ ⁼^27pF,

C

^p ⁼^470pF ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ⁹

2.4

R

L

= 2kΩ

^,

C

in =27pF,

C

p =470pF . . . 10

2.5 DUT input voltage . . . 11

2.6 DUT Current . . . 11

2.7 Lissajous urves. . . 12

2.14 Re tied voltage . . . 15

2.15 Re tied voltagemodifying

C

ⁱⁿ ^(right)^and

C

^p ^(left) ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ¹⁵

2.16 Cir uit layout . . . 16

2.17 Mask front andba k . . . 16

2.18 PICC built . . . 17

2.19 Measurement setup . . . 18

2.20

R

L

= 50Ω

^,

C

in =27pF,

C

p =470pF . . . 19

2.21

R

^L

= 1kΩ

^,

C

ⁱⁿ ⁼^27pF,

C

^p ⁼^470pF ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ²⁰

2.22

R

L

= 2kΩ

^,

C

in =27pF,

C

p =470pF . . . 21

2.23 Re tied voltage . . . 22

2.24 Re tied voltagemodifying

C

ⁱⁿ ^(right)^and

C

^p ^(left) ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ²²

2.25 Input voltage simulated and measured,

R

L sweep . . . 23

C

in sweep . . . 23

C

^p ^sweep ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ²⁴

2.28 FFT inputvoltage,

R

L

= 1.5kΩ

^,

C

in

= 27pF

^,

C

p

= 470pF

^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ²⁵

2.29 FFT inputvoltage,

R

L

= 500Ω

^,

C

in

= 10pF

^,

C

p

= 1nF

^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ²⁵

2.30 FFT input urrent,

R

L

= 1.5kΩ

^,

C

in

= 27pF

^,

C

p

= 470pF

^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ²⁶

2.31 FFT input urrent,

R

^L

= 500Ω

^,

C

ⁱⁿ

= 10pF

^,

C

^p

= 1nF

^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ²⁶

2.32 Re tied voltagesimulated and measured,

R

L sweep . . . 27

2.33 Re tied voltagesimulated and measured,

C

^sweep ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ^. ²⁷

(49)

3.5 TestPCD Assembly . . . 32

3.6 Resonan e frequen y measurement setup . . . 33

3.7 Resonan e frequen y ePassletSuite . . . 33

3.8 Resonan e frequen y lass1 PICC . . . 34

3.9 Testsetup . . . 35

3.10 Testsetup . . . 35

3.11 R2 valuesfor dierent magneti eldstrength . . . 36

3.12 S reenshot . . . 37

3.13 Testsetup . . . 38

3.14 CON2values for dierent magneti eldstrength . . . 38

(50)

[1℄ L.W.Mayer. Antennadesignforfuturemulti-standardandmulti-frequen yRFIDsystems.

PhD thesis, Institut für Na hri htente hnik und Ho hfrequenzte hnik, ViennaUniversity

of Te hnology,2009.

[2℄ Bi hlien HoangandAshley Caudill. A tive tagspassivetags.

[3℄ IEEE-USA Committee on Communi ations Poli y. The State of RFID Implementation

and ItsPoli y Impli ations: An IEEE-USAWhitePaper. IEEE,2009.

[4℄ Atmel orporation. Requierements of ISO/IEC 14443 Type B Conta tless Identi ation

Cards, 2005.

[5℄ Atmel orporation. Identi ation ards-Test methods. Part 6: Proximity ards, 2005.

[6℄ Nikola Gvozdenovi , Lukas W. Mayer, and Christoph F. Me klenbräuker. Measurement

of harmoni distortions andimpedan eof HFRFID hips. Te hni al report, 2013.

[7℄ Walter Bell. Investigation of fa tors inuen ing the non-linear input impedan e of a

onta tlessinputstage.Master'sthesis,InstitutfürElektronikderTe hnis henUniversität

Graz,2013.

[8℄ Rohde & S hwarz. Measurements on RFID Components A ording to ISO/IEC 14443

Standard,January2010.

[9℄ Sun Wai Hoong. RFIDTesting. Te hni al report, Rohde &S hwarz Systems and Com-

muni ations Asia,July 2009.

[10℄ ECMAInternational. ECMA-356, NFCIP-1 - RFInterfa e Test Methods, June 2004.

[11℄ Austrian institute of te hnology RFID Testlab. Test PCD Assembly. Te hni al report,

MIFARECerti ation institute, July 2009.

[12℄ WeiLin, BerndGe k, HermannEul, ChristianLans huetzer,andPeterRaggam. Anovel

methodfordeterminingtheresonan efrequen yofpi s.InCommuni ationSystems,Net-

works and Digital Signal Pro essing, 2008. CNSDSP 2008. 6th International Symposium

on,pages 311315. IEEE, 2008.

[13℄ Alexandre Tramoni, J-P Enguent, and Claude Tetelin. Method to simulate onta tless

systembasedons-parametersmeasurements. InWirelessTe hnology, 2005.The European

Conferen e on,pages 375378. IEEE, 2005.

[14℄ Wei Lin. Modellierung, Optimierung und Vermessen von HF-RFID-Transpondern unter

Simulación y medida de tarjetas sin contacto

ESCUELA TÉCNICA SUPERIOR DE INGENIERÍA DE TELECOMUNICACIÓN

UNIVERSIDAD POLITÉCNICA DE CARTAGENA

Proyecto Fin de Carrera

Simulación y medida de tarjetas sin contacto

AUTOR: Sandra Montoro Almendral DIRECTOR: Nikola Gvozdenovic, María Victoria Bueno y Christoph Mecklenbräuker

Julio / 2014

H min = 1.5A/m

H max = 7.5A/m

f s

f s

f c

1.8kΩ

0kΩ

2kΩ

220Ω

51kΩ

51Ω

500kΩ

110Ω

51Ω

1.5kΩ

C

C

R

R L = 50Ω, 500Ω, 1kΩ, 1.5kΩ, 2kΩ

C in = 10pF, 27pF, 47pF

C tp = 470pF, 1nF

C

C

R

1000 1050 1100 1150 1200

−3

−2

−1 0 1 2 3

ns

DUT voltage (V)

Simulated input voltage

−2dBm 5dBm 10dBm 15dBm 20dBm

−200 −150 −100 −50 0 50 100 150 200

−5 0 5 10 15 20 25 30 35

X: 15 Y: 24.11

frequency [MHz]

10 log 10 (DUTV freq )

Amplitude spectrum of input voltage

−2dBm 5dBm 10dBm 15dBm 20dBm

1000 1050 1100 1150 1200

−40

−30

−20

−10 0 10 20 30 40

ns

DUT current (mA)

Simulated input current

−2dBm 5dBm 10dBm 15dBm 20dBm

−200 −150 −100 −50 0 50 100 150 200

−35

−30

−25

−20

−15

−10

−5 0 5 10

X: 15 Y: 4.905

frequency [MHz]

10 log 10 (DUTC freq )

Amplitude spectrum of input current

−2dBm 5dBm 10dBm 15dBm 20dBm

−3 −2 −1 0 1 2 3

−40

−30

−20

−10 0 10 20 30 40

DUT current(mA)

DUT voltage (V) Lissajous curves

−2dBm 5dBm 10dBm 15dBm 20dBm

1000 0 1050 1100 1150 1200

0.2 0.4 0.6 0.8 1 1.2 1.4

ns

Rectified Voltage(V)

C _in = 10pF, 27pF, 47pF

C _tp = 470pF, 1nF