enhance cpw docstring
@@ -24,6 +24,9 @@ if TYPE_CHECKING:
class CPW(Media):
"""
+ Coplanar waveguide.
+
+
A coplanar waveguide transmission line is defined in terms of width,
spacing, and thickness on a given relative permittivity substrate of a
certain height. The line has a conductor resistivity and a tangential loss
@@ -47,9 +50,9 @@ class CPW(Media):
* Quasi-static characteristic impedance and effective permittivity model
use [GhNa84]_ and [GhNa83]_. The models are corrected to account for
- strip thickness using a first-order approach described in [GGBB96].
+ strip thickness using a first-order approach described in [GGBB96]_.
A comparison shows that ADS simulator uses another thickness correction
- method that is according to ADS doc based on [Cohn60]. This second method
+ method that is according to ADS doc based on [Cohn60]_. This second method
is not implemented in skrf.
* Frequency dispersion of impedance and effective permittivity model use
@@ -61,23 +64,25 @@ class CPW(Media):
Parameters
----------
frequency : :class:`~skrf.frequency.Frequency` object, optional
- frequency band of the media
+ frequency band of the media. The default is None.
z0 : number, array-like, or None (default None)
the port impedance for media. Only needed if different from the
characteristic impedance Z0 of the transmission line. In ohm
w : number, or array-like
- width of the center conductor, in m
+ width of the center conductor, in m. Default is 3e-3 m.
s : number, or array-like
- spacing (width of the gap), in m
+ spacing (width of the gap), in m. Default is 0.3e-3 m.
h : number, or array-like
- height of the substrate between backside and conductor, in m
+ height of the substrate between backside and conductor, in m.
+ Default is 1.55 m (equivalent to infinite height for default w and s).
t : number, or array-like, optional
conductor thickness, in m. Default is None (no width correction
to account for strip thickness).
has_metal_backside : bool, default False
If the backside is air (False) or metal (True)
ep_r : number, or array-like, optional
- relative permittivity of the substrate at frequency f_epr_tand, no unit
+ relative permittivity of the substrate at frequency f_epr_tand,
+ no unit. Default is 4.5.
diel : str
dielectric frequency dispersion model in:
@@ -85,17 +90,18 @@ class CPW(Media):
* 'frequencyinvariant'
rho : number, or array-like, or None
- resistivity of conductor, ohm / m
+ resistivity of conductor, ohm / m. Default is 1.68e-8 ohm /m (copper).
tand : number, or array-like
- dielectric loss factor at frequency f_epr_tand
+ dielectric loss factor at frequency f_epr_tand. Default is 0.
f_low : number, or array-like
lower frequency for wideband Debye Djordjevic/Svensson dielectric
- model, in Hz
+ model, in Hz. Default is 1 kHz.
f_high : number, or array-like
higher frequency for wideband Debye Djordjevic/Svensson dielectric
- model, in Hz
+ model, in Hz. Default is 1 THz.
f_epr_tand : number, or array-like
- measurement frequency for ep_r and tand of dielectric, in Hz
+ measurement frequency for ep_r and tand of dielectric, in Hz.
+ Default is 1 GHz.
compatibility_mode: str or None (default)
If set to 'qucs', following behaviour happens :
