Coplanar waveguide short

There is a similar simple approximation for a coplanar waveguide short-circuit, also given in [54]. The short circuit is inductive in nature.

Figure 12.4: coplanar waveguide short-circuit
\includegraphics[width=0.6\linewidth]{cpshort}

The equivalent length extension $ \Delta l$ associated with the fringing fields is

$\displaystyle \Delta l_{short} = \dfrac{L_{short}}{L'} \approx \dfrac{W + 2s}{8}$ (12.29)

Equation (12.29) is valid when the metalization thickness $ t$ does not become too large ($ t < s/3$).

The short end inductance $ L_{short}$ can be written in terms of the inductance per unit length and the wave resistance.

$\displaystyle L_{short} = L'\cdot \Delta l_{short} = \dfrac{\sqrt{\varepsilon_{r,eff}}\cdot Z_L}{c_0} \cdot \Delta l_{short}$ (12.30)

According to W.J.Getsinger [55] the CPW short-circuit inductance per unit length can also be modeled by

$\displaystyle L_{short} = \dfrac{2}{\pi}\cdot \varepsilon_0 \cdot \varepsilon_{...
...frac{\pi\cdot Z_{F0}}{2\cdot Z_L\cdot \sqrt{\varepsilon_{r,eff}}}\right)\right)$ (12.31)

based on his duality [56] theory.


This document was generated by Stefan Jahn on 2007-12-30 using latex2html.