Cell phone regulation on airlines?

On Wed, 13 Oct 2004 12:16:13 -0400, Ron Natalie
wrote:

G.R. Patterson III wrote:

Brian Case wrote:

Actually it could work very well, and I have seen this proposal from
several different sources. The Idea is to install a low power cell
phone tower into the airliner.


Well, it would work well, but not if they actually used the cellular frequencies
(AMPS). If they installed a PCS processor in the plane, modern PCS phones would
communicate with it and not fall back on the AMPS frequencies.

It would be a real can of worms. If everybody had a GSM phone in the
US it might be doable. But every carrier these days tends to market
a multimode phone that bounces between CDMA, old style TDMA, analog AMPS,
GSM, and a couple of proprietary schemes like iDEN.

Given that it's no big deal these days to make a multi-mode,
multi-band phone, why do you think it'd be so tough to make a
multi-mode, multi-band base station in the A/C? Certainly would be
easier if all phones were CDMA, of course. ;-)

Klein

On Wed, 13 Oct 2004 12:13:36 -0400, Ron Natalie
wrote:

Pooh Bear wrote:

The origin of the ban was due to concerns about cellphone transmissions
interfering with onboard avionics. This is more likely to be a concern with older
a/c. There is no hard data that I know of that substantiates the concern. There
is some anecdotal evidence of interference though.

Sorry, there are two issues. The FAA has it's own concerns about ANY
electronic devices. There's not hard and fast info on a lot of these
devices and the FAA has gotten more restrictive over time. However, the
AMPS regs specifically prohibit it without specifying the reason. It would
seem unlikely that a prohibition against airborn use however has anything
to do with air navigation because NOTHING ELSE the FCC regulates really
addresses that issue.


As another poster has mentioned, cellphones don't work well at altitude.

Wrong. AMPS / Analog cell phones, the ones the regulatory applies to, work
just fine from altitude. Actually too well. That was demonstrated on 9/11.
However some of the digital (PCS, for example) services, don't work at all
airborne (but they are not prohibited by regulation either).

Actually, PCS and 800 MHz digital CDMA work just fine airborne
provided there are only a few CDMA base stations near the aircraft,
but flying over a city it is hopeless. The problem is that in CDMA
systems many base stations transmit on the same wideband channel,
interfering with each other. The phone will never attempt to transmit
because it never succeeds in acquiring the system.

Klein

Teacherjh wrote:
It would be a real can of worms


The real answer is for the cell carriers to make deals with Airphone, so that
one could use Airphone units already installed on the airplane, and be billed
by ones cell carrier, at ones local rates.

That's sort of what Verizon has done.

Klein wrote:

Given that it's no big deal these days to make a multi-mode,
multi-band phone, why do you think it'd be so tough to make a
multi-mode, multi-band base station in the A/C? Certainly would be
easier if all phones were CDMA, of course. ;-)

That would be fine if there were some industry cooperation with the
people planning on offering the airborne service. But the plethora
of incompatible modulation schemes now sort of demonstrates that this
level of cooperation isn't likely .

The real answer is for the cell carriers to make deals with Airphone, so that

That's sort of what Verizon has done.


Right. But if every carrier did it, we'd be all set.

Jose

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