Bob,

I don't believe that we switch to GSM or whatever.

1. For none of the digital communication techniques it was possible to
find a global frequency range.

2. The relative speed is too high. To my knowledge the highest speed to
which a digital communication system is certified is 500 km/h (310 mph).
This is GSM-R, Global System for Mobile Communications - Railway or
GSM-Railway, for details see Wikipedia.
500km/h would be good enough for us but not for others. We can forget it
in aviation thanks to Doppler effect.

Bear


On 12.04.2013 04:12, Bob Kuykendall wrote:
On Apr 11, 2:33 pm, "Paul Remde" wrote:
... At a recent soaring
seminar someone stated that they thought the FAA was
going to require radios with the 8.33 MHz spacing starting in 2020.

I will be someewhat surprised if we get to 2020 and we are still using
what we think of today as "aircraft radios." I think that by then we
will find that the bandwidth dedicated to those old grampa boxes will
have been divided up and auctioned off, and we will be communicating
over a system based on mobile phone infrastructure.

If I'm wrong, I'll buy you a beer at the 2020 SSA convention. Offer
limited to the first 24 "I told ya sos."

Thanks, Bob K.