Alan wrote:
In article Eric Greenwell writes:

And yet, I can have good service on the ground, but poor or no service
in the air, over the same area. It's not about obstacles, but antenna
patterns, power, and how the system handles a phone that is reaching
multiple towers.

My point exactly.

In the air, your phone hears multiple cell transmitters on each frequency.
It may have difficulty finding a channel where it can clearly hear the
control information.

That sounds like a pretty good explanation. Would that explain why the
the signal strength display (number of bars shown) is low or zero? The
lack of bars is what makes me think the power drops off with altitude
enough to stop the phone from working, but maybe that's incorrect.

Your explanation also doesn't explain why when the cellphone doesn't work
while standing on the mountain top next to the suburban area, walking behind
a building to shield the phone from the view of so many cell towers causes it
to start working. The angles from the cell towers don't change.

I haven't tried that, but it does suggest the phone in the glider should
be shielded so it uses signals in only one direction as a way to improve
it's operation. Tough to do while circling, but maybe it'd be practical
in straight flight.


--
Eric Greenwell - Washington State, USA
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* Updated! "Transponders in Sailplanes" http://tinyurl.com/y739x4
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