Capacitor

During DC simulation the capacitor is an open circuit. Thus, its MNA entries are all zero.

During AC simulation the y-parameter matrix of an ideal capacitor with the capacitance $C$ writes as follows.

$$Y = \begin{pmatrix}+j\omega C & -j\omega C\\ -j\omega C & +j\omega C\\ \end{pmatrix}$$ (9.10)

The scattering parameters (normalized to $Z_0$) of an ideal capacitor with capacitance $C$ writes as follows.

$$S_{11} = S_{22} = \frac{1}{2\cdot Z_0\cdot j\omega C+1} \\$$ (9.11)

$$S_{12} = S_{21} = 1-S_{11}$$ (9.12)

An ideal capacitor is noise free. Its noise correlation matrices are, therefore, zero.