In the case of gap sources on metal traces and probe sources on PEC vias, turning a source off means shorting a series voltage source. The electric currents passing through these sources are then found at each port location, and the admittance parameters are found as follows:
:<math> I_m = \sum_{n=1}^N Y_{mn} V_n, \quad \quad Y_{mn} = \frac{I_m}{V_n} \bigg|_{V_k=0, k \ne n}</math><!--[[File:PMOM57.png]]-->
In the case of gap sources on slot traces, turning a source off means opening a shunt filament current source. The magnetic currents passing through the source locations, and thus the voltages across them, are then found at all ports, and the impedance parameters are found as follows:
:<math> V_m = \sum_{n=1}^N Z_{mn} I_n, \quad \quad Z_{mn} = \frac{V_m}{I_n} \bigg|_{I_k=0, k \ne n}</math><!--[[File:PMOM58.png]]-->
The N solution vectors that are generated through the N binary excitation analyses are finally superposed to produce the actual solution to the problem. However, in this process, EM.Cube also calculates all the port characteristics. Keep in mind that the impedance (Z) and admittance (Y) matrices are inverse of each other. From the impedance matrix, the scattering matrix is calculated using the following relation:
:<math> \mathbf{[S] = [Y_0] \cdot ([Z]-[Z_0]) \cdot ([Z]+[Z_0])^{-1} \cdot [Z_0]} </math><!--[[File:PMOM63.png]]-->
where ['''Z<submath>0\mathbf{[Z_0]}</submath>'''] and ['''Y<submath>0\mathbf{[Y_0]}</submath>'''] are diagonal matrices whose diagonal elements are the port characteristic impedances and admittances, respectively.
=== Modeling Lumped Elements In Planar MoM ===