Using mobiles in an aeroplane... NOT dangerous after all! (apparently)

On Fri, 15 Oct 2004 18:15:54 -0000, "Ivor Jones"
wrote:

From personal experience, all flights I've been on in the last few years
allow phones to be used while the aircraft is on the ground and at the
gate with the doors open.

this is highly airline specific. Lufthansa will not let you use
"handys" in the cabin at all. Northwest will allow you to use them
once the plane touches down and is taxiing, but on departure only
until the door is closed etc etc.

I have seen pilots / co-pilots using their phones while parked up and
train drivers while the train is moving.

Phil
--
spamcop.net address commissioned 18/06/04
Come on down !

"JamesUK" wrote in message
news

"nobody" wrote in message
...
Clueless2 wrote:
isn't the issue. OTOH, GSM was designed to hand handoffs up to about
150kph
and most commercial airliners fly at a much higher speed than this
limit.

However, at altitude, your distance to a ground antenna does not change
as
fast as the aircraft moves, whereas on the ground it changes as fast as
your
car/train travels.

It would actually change faster.

The ground speed is greater, and hence distance moved over the ground is
greater. However, the point to point distance between aircraft and an the
base station on the ground would depend on the altitude of the aircraft over
the base station. Simple trigonometry. You don't have to know trig. Just
draw it on on a bit of paper. Far - Near - Far, and see how the lines
change proportions.

--
Andy.

"JamesUK" wrote in message
news

"nobody" wrote in message
...
Clueless2 wrote:
isn't the issue. OTOH, GSM was designed to hand handoffs up to about
150kph
and most commercial airliners fly at a much higher speed than this
limit.

However, at altitude, your distance to a ground antenna does not change
as
fast as the aircraft moves, whereas on the ground it changes as fast as
your
car/train travels.

It would actually change faster.

The ground speed is greater, and hence distance moved over the ground is
greater. However, the point to point distance between aircraft and an the
base station on the ground would depend on the altitude of the aircraft over
the base station. Simple trigonometry. You don't have to know trig. Just
draw it on on a bit of paper. Far - Near - Far, and see how the lines
change proportions.

--
Andy.

"JamesUK" wrote in message
news

"nobody" wrote in message
...
Clueless2 wrote:
isn't the issue. OTOH, GSM was designed to hand handoffs up to about
150kph
and most commercial airliners fly at a much higher speed than this
limit.

However, at altitude, your distance to a ground antenna does not change
as
fast as the aircraft moves, whereas on the ground it changes as fast as
your
car/train travels.

It would actually change faster.

The ground speed is greater, and hence distance moved over the ground is
greater. However, the point to point distance between aircraft and an the
base station on the ground would depend on the altitude of the aircraft over
the base station. Simple trigonometry. You don't have to know trig. Just
draw it on on a bit of paper. Far - Near - Far, and see how the lines
change proportions.

--
Andy.

Ivor Jones reckoned that...
In any case, avionics problems aside, how many cell sites do you think
you're going to access at 30,000 feet..?!

I would imagine there will be some other form of carrier to link the
aircraft with a ground-based installation.
--
www.unlockingshop.co.uk
K700i unlock/unbrand £22.50

Ivor Jones reckoned that...
In any case, avionics problems aside, how many cell sites do you think
you're going to access at 30,000 feet..?!

I would imagine there will be some other form of carrier to link the
aircraft with a ground-based installation.
--
www.unlockingshop.co.uk
K700i unlock/unbrand £22.50

In uk.telecom.mobile nobody wrote:
snip
The tests that have been made and which will lead to mobile phone service in
2006. But it requres the installation of what is called a picocell
(essentially an antenna) inside the cabin. This will allow the phones to
operate are a much lower power level and their emissions won't reach the ground.

The plane will relay calls over satellite back to the ground. And tel'll
probably ding you for mobile roaming fees, but that will be charged to your
mobile phone bill.

Idly wondering what will happen if the phone is locked to a network other
than the picocell one.
Surely it'll go to full power and start pinging away at whatever networks
it can reach outside the plane?

In uk.telecom.mobile nobody wrote:
snip
The tests that have been made and which will lead to mobile phone service in
2006. But it requres the installation of what is called a picocell
(essentially an antenna) inside the cabin. This will allow the phones to
operate are a much lower power level and their emissions won't reach the ground.

The plane will relay calls over satellite back to the ground. And tel'll
probably ding you for mobile roaming fees, but that will be charged to your
mobile phone bill.

Idly wondering what will happen if the phone is locked to a network other
than the picocell one.
Surely it'll go to full power and start pinging away at whatever networks
it can reach outside the plane?

In uk.telecom.mobile wrote:
"Clueless2" no.spam wrote in message
:

GSM phones are designed to work up to a distance of 35km (double this
distance if only every other time-slot is used) so working at 35,000 feet
isn't the issue. OTOH, GSM was designed to hand handoffs up to about 150kph
and most commercial airliners fly at a much higher speed than this limit.

You remember incorrectly.

Nowhere in the phase 2 (or later) GSM standards was there any mention of
speed apart from in the propagation profiles where, IIRC the maximum
speed modeled was 250km/h for 900MHz and 130km/h for 1800MHz.

The systems managed to perform at speeds well in excess of this. I've
not seen anything anywhere giving a maximum speed as a design criteria

If I was to buy a small ocean-going yaught, equip it with a satellite
uplink and a GSM base station with several high-gain antennas that I
pointed at airplanes passing over in the flight path I was parked next
to, is it possible to tweak the range further, at the expense of
capacity?
(idly wondering)

In uk.telecom.mobile wrote:
"Clueless2" no.spam wrote in message
:

GSM phones are designed to work up to a distance of 35km (double this
distance if only every other time-slot is used) so working at 35,000 feet
isn't the issue. OTOH, GSM was designed to hand handoffs up to about 150kph
and most commercial airliners fly at a much higher speed than this limit.

You remember incorrectly.

Nowhere in the phase 2 (or later) GSM standards was there any mention of
speed apart from in the propagation profiles where, IIRC the maximum
speed modeled was 250km/h for 900MHz and 130km/h for 1800MHz.

The systems managed to perform at speeds well in excess of this. I've
not seen anything anywhere giving a maximum speed as a design criteria

If I was to buy a small ocean-going yaught, equip it with a satellite
uplink and a GSM base station with several high-gain antennas that I
pointed at airplanes passing over in the flight path I was parked next
to, is it possible to tweak the range further, at the expense of
capacity?
(idly wondering)