On 6/14/17 10:44 AM, JVarney wrote:
Thanks Kurt for the very interesting history of
how antenna square footages came to be. If we walk
through TIA-222-G it will illustrate Kurt's point that
just giving a square footage isn't that helpful:
====
Gh is a "gust factor"
EPA is the Effective Projected Area
(EPA) = Ka[(EPA)N cos2(θ) + (EPA)T sin2(θ)]
I think you have to evaluate the above at "all angles" and pick the
worst case
Yeah, it really comes down to either giving the breakdown of actual
projected areas, and let the user figure out the final EPA for their
particular exposure, or give a fairly complete table.
The computations aren't hideously complex, but aren't something I'd want
to do with a hand calculator or slide rule. So If I were manufacturer
who wanted to be helpful, I'd pick some representative situations and
run the calculations for those, but also give all the assumptions (gust
factors, etc.)
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