I'm not convinced of that. In a truly lossless line,
characteristic impedence Z0 = [ L0/C0 ]^0.5 where L0
and C0 are per length parameters of inductance and
capacitance respectively. So that theoretically, a
2 inch trace should have the same CI of a 20 inch trace.
> When a meander is added, it alters the geometry.
Agreed.
> If the curvature is tight enough, then the AC field
> distribution will be noticeably different in the region
> of the meander than for some distant segment.
I'm in absolute agreement up to here.
> We observe
>this as an increase in the apparent capacitance per unit length in the
>region of the meander.
Here's where I diverge. The lumped parameter model
from which CI is derived (I'm sure you're aware, but
for sake of the discussion) takes on the form
R L
+/\/\/\mmmm+ ...

 C


++ ...
 < dx > 
For a lossless line, R=0.
What I was suggesting with my drawing in a previous
post is that meandering causes parasitic capacitance
in parallel with the trace is the following model
Cp
+ +
 
 L 
++mmmm+ ...

 C


++ ...
 < dx > 
And some shunting of the trace inductance is achieved.
And thus, the reason for reduced CI.
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