NEC-LIST: Infinite periodic structure

'day,

I'd like to model railway overhead power lines used as a transmission
line, in order to determine their usability for data transmission from
a locomotive through the pantograph.

Before I go on, I'd first like to say that I'm expecting rather
limited formance. Namely, high impedance, large cross coupling with
adjacent lines, appearance of higher order modes.

My idea is that at low frequency the line can be seen as a TEM
transmission line, and that at some frequency some first superior mode
will appear, where the usefulness of the line will decrease.

Basically I'd like to find the low frequency transmission line
parametres of the line. Hopefully I'd get some results at at frequency
where I don't run into the segment length limitations of NEC2, and
extrapolate down. At higher frequencies I'd like to check the way the
line would radiate, and were the first modes appear.

But before that, and the reason why I'm addressing my call to this
list, is how I could go about modeling an INFINITE line from only a
SINGLE section strung from a pole. Was this done? How could I go about
this? I don't mind writing pre- or post-processing programs.

Thanks,

Alexandre
Received on Mon Nov 13 2000 - 15:03:46 EST