Input Reflection Coefficient

1

1

0

0

L

L

L

Lin z

z

ZZ

ZZ

Let LLL jxrz irL jand

ir

irLL j

jjxr

1

1

2

2

2

1

1

1

LL

Lr rr

ri

22

2 111

LLir xx

2

2

2

1

1

1

LL

Lr rr

ri

rL = 0 --> ZL=jXL

rL = ∞

rL = 1 --> ZL=1+jXL

22

2 111

LLir xx

xL = 1

xL = -0.5

Complete Chart

Constant-r circles Constant-x circles

Phillip SmithRead a brief biography of Philip Smith: http://sss-mag.com/smith01.html

Black MagicDesign

What Can We Do with the Smith Chart?

• Reading Reflection Coefficient, Impedance/admittance, SWR(VSWR), Return Loss, …

• Impedance Matching

• Locating the load on the chart

• Moving around on the chart

Reading Reflection Coefficient

ΓL = 0.725/125°0.725 125°

Open? Short? Matched Load?

ZL = 10+j25 Ω

zL = 0.2+j0.5

And more …

Reading Load Impedance ΓL = 0.5/-90°

zL = 0.6-j0.8

ZL = 30-j40 Ω

If Z0 = 50 Ω