Smith Chart

Smith Chart

Microwave EngineeringMicrowave EngineeringCHO, Yong HeuiCHO, Yong Heui

Microwave Microwave EngineeringEngineering

EM Wave EM Wave LabLab

2

Photo of Smith chart

Graphical method

Essential diagram for microwave engineering

1. Smith chart

P. Smith in 1939



3

Induction of Smith chart

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LL

L

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L

L

j

j

zz

z

Z

jXR

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e

1

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1

1

z

:impedance load Normalized

1|| where||

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0

0

1. Smith chart



4

Induction of Smith chart

2222

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1

1

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ir

i

ir

ir

ir

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xr

j

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1

1

1

xxrr

ririr

Circle equations

1. Smith chart



5

Constant resistance circles

1

1

1

22

2

rr

rir

1. Smith chart



6

Constant reactance circles

22

2 111

xxir

1. Smith chart



7

Input impedance

zjzj

zjzj

s

sinin

zjzjs

zjzjos

ee

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)2(

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2

2

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1

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At

lj

lj

lj

lj

in e

e

e

ez

lz

1. Smith chart



8

Input impedance

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chart.Smith on the 2 of angle Clockwise

2

l

l

l

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1. Smith chart



9

Admittance

)2(

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2

2

1

1

1

1

1

lj

lj

lj

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e

e

e

e

zy

1. Smith chart



10

2. Applications

VNA (Vector Network Analyzer)

Measurement equipment

Reflection coefficients with frequency sweep



11

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APoint 1 5.0

15.0

line -50 aon 5025

xr

jz

jZ

L

L

Representation of Smith chart

2. Applications

Smith Chart

Technology

Transcript of Smith Chart