Tool 08 · Available

Smith Chart Explorer

Move between normalized impedance, admittance, and reflection-coefficient views analytically.

Engineering question

Where does this impedance map in the reflection-coefficient plane?

Analytic Smith chart

Exact inputs are authoritative; pointer movement is a convenient constrained Γ control. Stored points remain only in this bounded page session.

Geometry invariants
Smith chart reflection planeAnalytic constant-resistance and reactance grid. Centre is matched, left is short, right is open, upper impedance half is inductive, and lower is capacitive.matchshortopen+jX inductive−jX capacitivecurrent
Reflection coordinate0.333333 + j0.000000|Γ| 0.333333 ∠ 0.000°

The point is in the inner half on the real axis. Moving the reference plane on a lossless line rotates it without changing |Γ|.

Impedance Z
100.00000 + j0.00000 Ω
Normalized z
2.00000 + j0.00000
Admittance Y
10.00000 + j0.00000 mS
Normalized y
0.50000 + j0.00000
VSWR
2.00000
Return loss
9.54243 dB
Mismatch loss
0.51153 dB
Reference plane
Z₀ = 50.0000 Ω
Every plotted point has a textual Γ equivalent.
PointΓ realΓ imaginary|Γ|Phase
Current0.3333330.0000000.3333330.000°

Calculation path

  1. z=ZZ0y=1zz = \frac{Z}{Z_{0}}\qquad y = \frac{1}{z}
  2. Γ=z1z+1\Gamma = \frac{z-1}{z+1}
  3. For the e^(jωt) convention, moving toward the generator rotates Γ clockwise; toward the load rotates it counter-clockwise.

What this calculator is doing

The chart is the unit-circle mapping Γ = (z−1)/(z+1). Analytic constant-resistance and constant-reactance loci accompany pointer-to-Γ conversion.

How to read the result

Read the chart as a transformation plane, not a component value. Retain the reference impedance and reference-plane location with every point.

Equations & conventions

  • z=ZZ0z = \frac{Z}{Z_{0}}
  • Γ=z1z+1\Gamma = \frac{z-1}{z+1}
  • y=1zy = \frac{1}{z}
  • z = Z/Z0 is normalized impedance; y = 1/z is normalized admittance.
  • The chart centre is Γ = 0 and its boundary is |Γ| = 1.
  • Z0 is a positive real normalization impedance.

Independently checked example

Checked example: 100 + j0 Ω normalized to 50 Ω is z = 2 + j0 and Γ = 0.333333 + j0 at VSWR 2.

Common mistakes

  • Reading an unlabelled point without knowing Z0.
  • Treating chart grid lines as measured accuracy.

Assumptions, validity & omissions

  • Z₀ is positive and real.
  • Passive positive-resistance loads map inside the unit circle.
  • Chart geometry is analytic; the grid is not measured data.

Sources & model provenance

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