W-Element Options

Option

Default Value

Description

w_element.enforce_causality

1

1=Ensure the input data is causal (satisfies the Kramer-Kronig and Hilbert-transform relations)

0=No causality enforcement

w_element.enforce_passivity

0

0=No passivity enforcement

1=Enforce the passivity of the state-space model during transient analysis of S-parameter element

2= Use a point-by-point method for enforcing passivity. Use this option in cases with large numbers of ports (more than about 30).

6=Use a passivity by perturbation algorithm.

Setting enforce_passivity=2 automatically sets mor=3, since this passivity enforcement algorithm requires this model-order reduction strategy.

w_element.fdie

1e9

Frequency at which the capacitance matrix is specified, for Hilbert causality correction

w_element.g_to_gnd

1e-12

Conductance between all terminal nodes of all W-elements and ground

w_element.hspice_skin

0

1=turn on HSPICE skin effect model
(non-causal, ignores internal inductance)

w_element.ignore_losses

0

1=Generate lossless model (ignoring R and G)

w_element.min_freq_count

100

Minimum number of frequencies required in TABLE model. If fewer frequencies are present, the table will be interpolated up to the specified minimum.

w_element.mor

0

0=No model order reduction (MOR)

1=MOR of entire matrix at once

2=MOR of rows of matrix individually, then final MOR for the combination

3=MOR of rows of matrix individually, no final MOR

4=MOR of columns of matrix individually, then final MOR for the combination

5=MOR of columns of matrix individually, no final MOR

w_element.reltol

1e-2

Relative tolerance to apply to currents and voltages during analysis

w_element.time_domain_w_model

0

1=create state-space system, even in a frequency-domain analysis like LNA where one is not usually generated. It won’t be passive unless s_element.enforce_passivity=1