Re: NEC-LIST: Can Is as Can Do

George,

Although I am grateful that we have modern computational tools to give
us an indication of certain trends that wire antennas will have
without actually having to measure them, I have difficulty agreeing
with you that modern computational tools have replaced good
measurement practices. I think that even the availabilty of moment
method codes in Wheeler's day would not have done away with the need
for the radiansphere. I have performed measurements as well as
modelled wire antennas using MOM based programs and rarely found that
the two were in agreement. I admit that I am not as proficient in NEC
modelling as some of the very talented people on this email list.
However, I have worked in parallel with other engineers on the same
projects where they were trying to use MOM codes to predict antenna
performance while I was doing the actual measurements. I noticed that
the initial NEC predictions were in error, and that only after
repeated refinements of the NEC models and comparing them with
measurements, were the predictions acceptible. In other words, if you
have to peak at the measurement data to get the model right, then you
really aren't predicting the performance. Measurements have always
and still do have an important place in antenna engineering, even with
the availabilty of modern computational tools.

Roland
Received on Thu Apr 22 1999 - 17:45:06 EDT