At 11 Nov 2006 20:34:30 +0000 John Richards wrote:

> Physics says that RF path propagation loss consists of two components:
> Free Space Loss, and loss caused by absorption and scattering from
> buildings and vegetation (trees) in the path.

Bah, what does physics know? ;-)>

> Free Space loss is proportional to the operating frequency:
> http://en.wikipedia.org/wiki/Free-space_loss
>
> Using one of the commonly available online calculators, it is evident
that
> free space loss is increased approximately 7dB when changing the
operating frequency from 850MHz to 1900MHz:
> http://www.terabeam.com/support/calc...space-loss.php

It think the point John Navas may be making (or, perhaps,
misinterpreting!) is that in most metro areas this is largely irrelevant,
since so many "extra" towers are needed to support the capacity load that
the propagation loss caused by distance of each individual tower is
generally moot.

Obviously in rural areas the 800MHz carriers have an advantage where
capacity isn't an issue, and distance is the limiting factor.

I remember in the late 80's a rural Nebraska cellular carrier (aptly
named "Nebraska Cellular") managed to provide excellent cellular service
along I-80 through almost the entire state with a minimal number of
towers thanks to 800MHz propagation and some VERY flat terrain!

Off topic, but interesting, one of their head honchos told me (back then)
that they made half of their total revenue from roamers (this was back
in the old $3/day + $1/minute roaming days) so highway coverage was more
important to them than covering the towns they serviced!



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