Wave impedance of coplanar line when hyperbolic sine ratio squared is between \(0\) and \(\frac{1}{2}\)

Under the conditions described below, the wave impedance of a coplanar line depends on its effective permittivity and physical dimensions.

Conditions:

  1. \(h < \frac{d}{4}\)

  2. \(0 < \left( \frac{\sinh{ \left((\pi l) / (4 h)\right) }}{\sinh{ \left((\pi d) / (4 h)\right) }} \right)^2 \le \frac{1}{2}\)

See below for symbol descriptions.

wave_impedance

wave_impedance of the coplanar line.

Symbol:

eta

Latex:

\(\eta\)

Dimension:

impedance

effective_permittivity

Effective relative_permittivity of the coplanar line. See Effective permittivity of coplanar line.

Symbol:

epsilon_eff

Latex:

\(\varepsilon_\text{eff}\)

Dimension:

dimensionless

electrode_distance

euclidean_distance between the first and last electrodes.

Symbol:

d

Latex:

\(d\)

Dimension:

length

central_electrode_width

Width (see length) of the central electrode of the coplanar line.

Symbol:

l

Latex:

\(l\)

Dimension:

length

resistance_constant

Constant equal to \(30 \, \Omega\) (30 Ohm).

Symbol:

R_0

Latex:

\(R_0\)

Dimension:

impedance

law

eta = R_0 / sqrt(epsilon_eff) * log(2 * (1 + (1 - (l / d)^2)^(1 / 4)) / (1 - (1 - (l / d)^2)^(1 / 4)))

Latex:
\[\eta = \frac{R_0}{\sqrt{\varepsilon_\text{eff}}} \log \left( \frac{2 \left(1 + \left(1 - \left(\frac{l}{d}\right)^{2}\right)^{\frac{1}{4}}\right)}{1 - \left(1 - \left(\frac{l}{d}\right)^{2}\right)^{\frac{1}{4}}} \right)\]