A long time ago, when there was not so much man-made noise, I found that in
the almost-flat-country at the extreme edges of coverage from a base station
to a mobile station, the rate of decrease was roughly one db per statute
mile. This was in the 160 MHz range.
The mobile is so far away from the base that the received signal is
"noisy." I am considering rural locations and a terrain without significant
hills.

On the average, +3db of power at the base provided another 3 miles of
(poor quality) coverage. More often than not, coverage was limited by the
transmitter power of the mobile and the noise level at the base!

The question asked can start to be answered when one knows the value
placed on increased coverage.

73 Mac N8TT
--
J. Mc Laughlin; Michigan U.S.A.
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