I noticed on the evening news the other night that someone is trying to get
a modular mobile "cell tower" approved that would be installed in commercial
aircraft so that passengers can use their own mobile phones. It will be
interesting to see how the FCC and FAA handle this one.

--
Bob (Chief Pilot, White Knuckle Airways)

I don't have to like Bush and Cheney (Or Kerry, for that matter) to love
America

"Ron Natalie" wrote in message
m...
DaveC wrote:
Cell phone usage is restricted on all domestic commercial flights by the
FAA,
so the flight attendant keeps telling me.

Nope. The FAA rules have not changed on this, nor have the FCC ones.
You can't use Advanced Mobile Phone Service (i.e., traditional cellular)
airborne. That is an FCC rule.

The FAA rule is just that the airline (i.e., the operator) must
determine when electronic devices are safe to use. The only thing that
has really changed is the "conventional wisdom" on the FAA's part got a
little tighter after some supposed interference issues (primarily blamed
on laptops) a few years back.

Is cell phone usage also restricted on private jets, etc. for similar
reasons?

Yes, all airborne use is prohibited. On cell phones permanently
installed on private jets, there has to be a warning label attached to
prohibit it's use in the air. (FCC rule).

So my question... what is the technical reason for restriction of cell
phone
us on commercial flights? Is this reason valid, technically? Or is it
simply
an excuse to force anyone who needs to make a call to use the airline's
on-board phones (and pay their outrageous rates)?

Forcing you to use the Airphones is the least of the FAA's or the FCC's
concern.

The real reason is that the cellular phone industry does not want you
to. Their bread and butter is the ground based caller, and their
systems are not designed to work with callers that have some altitude on
the system (there are techncial deficiencies in this that I won't go
into unless you really want to know). As a matter of fact, the cellular
industry fought a company who wanted to share the spectrum
tooth-and-nail over airborne use.

Oddly, this prohibition is NOT written into the rules for the newer
wireless services (PCS, NEXTEL, etc...) that operate outside the AMPS
(800MHz) band. However, most of the carriers with these services still
discourate airborne use.

"Bob Chilcoat" wrote in message
...
I noticed on the evening news the other night that someone is trying to
get
a modular mobile "cell tower" approved that would be installed in
commercial
aircraft so that passengers can use their own mobile phones. It will be
interesting to see how the FCC and FAA handle this one.

--
Bob (Chief Pilot, White Knuckle Airways)


Still won't work. The frequency the cell in the air is on, will be hitting
dozens of towers on the ground, making them unable to use that frequency for
other users on the land.
--
Jim in NC


---
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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.

As I understand it that signal bar you see on you Cell phone is
dictates how much power the cell phone uses to transmit. So the closer
you are to the tower the less power it uses to transmit. This is why
you phone batteries probably last longer in town than the do out in
the boondocks.

By installing the tower in the aircraft you are only a few hundred
feet from the tower (at the most). The Cell phones will get an
excellent signal from it and will drop to the lowest transmit power
setting, Thus the interference with towers on the ground should be
minimal.

I am not an expert on these, I am just repeating how it was explained
to me.

Brian

"Morgans" wrote in message ...
"Bob Chilcoat" wrote in message
...
I noticed on the evening news the other night that someone is trying to
get
a modular mobile "cell tower" approved that would be installed in
commercial
aircraft so that passengers can use their own mobile phones. It will be
interesting to see how the FCC and FAA handle this one.

--
Bob (Chief Pilot, White Knuckle Airways)


Still won't work. The frequency the cell in the air is on, will be hitting
dozens of towers on the ground, making them unable to use that frequency for
other users on the land.

Brian Case wrote:


As I understand it that signal bar you see on you Cell phone is
dictates how much power the cell phone uses to transmit. So the closer
you are to the tower the less power it uses to transmit. This is why
you phone batteries probably last longer in town than the do out in
the boondocks.

The cellular phone does use an adaptive power control (it's not tied to
the signal strength bar).

The problem is that even at mimimal power, if you're sitting close to
the window, you can be heard equally well by a large number of cells
over the system. There's nothing magic that they can do to stop this
short of rf shielding the aircraft windows somehow.

"Brian Case" wrote in message
om...
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.

As I understand it that signal bar you see on you Cell phone is
dictates how much power the cell phone uses to transmit. So the closer
you are to the tower the less power it uses to transmit. This is why
you phone batteries probably last longer in town than the do out in
the boondocks.

By installing the tower in the aircraft you are only a few hundred
feet from the tower (at the most). The Cell phones will get an
excellent signal from it and will drop to the lowest transmit power
setting, Thus the interference with towers on the ground should be
minimal.

I am not an expert on these, I am just repeating how it was explained
to me.

Brian
I could see the possibilities of strong enough signal not reaching the
ground to cause problems, but......

Which company (Of the multitudes) will you have to belong to, to get your
phone to work? How will the plane's system communicate with the ground? By
cell tower? g
--
Jim in NC


---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
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The only thing that I see wrong with this is that the cell "tower" needs
to connect to the wired phone system. We know that it can't be
hardwired, that would be one hell of a long cable! So, as the "tower"
needs to transmit and receive (transceiver) from other transceivers on
the ground that are hardwired to the phone system. You can put the
ground transceivers on a different frequency pairs, but that's a whole
new world wide system!

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.

As I understand it that signal bar you see on you Cell phone is
dictates how much power the cell phone uses to transmit. So the closer
you are to the tower the less power it uses to transmit. This is why
you phone batteries probably last longer in town than the do out in
the boondocks.

By installing the tower in the aircraft you are only a few hundred
feet from the tower (at the most). The Cell phones will get an
excellent signal from it and will drop to the lowest transmit power
setting, Thus the interference with towers on the ground should be
minimal.

I am not an expert on these, I am just repeating how it was explained
to me.

Brian

"Morgans" wrote in message ...

"Bob Chilcoat" wrote in message
...

I noticed on the evening news the other night that someone is trying to

get

a modular mobile "cell tower" approved that would be installed in

commercial

aircraft so that passengers can use their own mobile phones. It will be
interesting to see how the FCC and FAA handle this one.

--
Bob (Chief Pilot, White Knuckle Airways)


Still won't work. The frequency the cell in the air is on, will be hitting
dozens of towers on the ground, making them unable to use that frequency for
other users on the land.

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.

George Patterson
If a man gets into a fight 3,000 miles away from home, he *had* to have
been looking for it.

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.

It's going to have to be a "only [insert carrier here]" phones work onboard
United's flights.

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

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 .