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Transmission Line Parameters of a Wire Pair




Center-to-Center Spacing

Wire Diameter

Conductor Material

Conductivity: σ =


Dielectric Material

Relative permittivity: εr =


Inductance per unit length

 μH per 

Capacitance per unit length

 pF per  

Resistance per unit length

 mΩ per 

Characteristic Impedance


wire pair transmission line equations

Instructions: Enter the frequency, center-to-center spacing, and wire diameter. If you want to specify a conductor other than copper, choose "custom" and specify the conductivity of the conductor material. If you want to specify a dielectric other than air, choose one of the other optional materials or choose "custom" and specify the relative permittivity of the dielectric. Click the "Calculate" button to show the calculated transmission line parameters. Per-unit-length parameters are "per meter" if the center-to-center spacing units are cm or mm. They are "per foot" if the center-to-center spacing units are inches or mils.

Note: All materials are non-magnetic (i.e. μ = μ0). Dielectric losses are not modeled.

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