View Full Version : Opposition to Airborne Cell Phones Floods FCC
17th Dec 2004, 20:01
Opposition to Airborne Cell Phones Floods FCC
Thu Dec 16, 6:06 PM ET U.S. National - Reuters
By Jeremy Pelofsky
WASHINGTON (Reuters) - U.S. air travelers wasted little time barraging communications regulators with hundreds of e-mails registering their opposition to ending the ban on the use of mobile phones during commercial flights.
The U.S. Federal Communications Commission (news - web sites) on Wednesday unanimously proposed lifting the ban if issues about safety and technical hurdles can be overcome. FCC (news - web sites) officials said their mandate was to facilitate communications.
But the potential of scores of passengers talking on mobile phones during a lengthy flight has many travelers worried that their last quiet haven from such conversations will evaporate.
"We've received a couple hundred e-mails from the public, most of whom believe that use of devices that don't involve talking are fine, but are not looking forward to the possibility of hearing more conversations than they do now," said Lauren Patrich, a spokeswoman for the FCC wireless bureau.
The FCC's consumer bureau also received more than 1,200 e-mails on the subject.
During a meeting on Wednesday to adopt the proposal, FCC commissioners acknowledged their hesitation at the impact of allowing air travelers to use their wireless phones while aloft but said those decisions were outside the agency's purview.
The U.S. Federal Aviation Administration (news - web sites) also has a ban against the use of communications devices aboard airplanes. Officials from both agencies have said it will probably be two years before the ban could be lifted, if at all.
Some who sent comments to the FCC expressing fears suggested that if the ban is lifted and wireless service is allowed on board, the airlines should separate those who want to use their phones behind a partition.
Another person worried that the airlines could start charging a premium to passengers who want a flight that does not allow the use of mobile phones.
Amtrak rail service in the northeast section of the United States, including its flagship route between Boston and Washington, offers one car on most trains where wireless phones are banned and conversation must be kept to a whisper at most.
The so-called quiet car was instituted after Amtrak received a request from a frequent passenger who had grown tired of the increasing volume of fellow travelers using their phones, according to Amtrak spokesman Cliff Black.
"We decided to give it a try as a pilot ( :yuk: ) project and it was very popular," he said. "Eventually it has spread.
Do the new phones not interfere with the navigation signals?
I thought that the reason portable communication devcices were not allowed was because the possibilty of the radio transmission of said devices intefering with radio navigation ?
Having spent the last couple of days playing with VoIP (Voice over IP) - or as one of our more technolgy orientated members pointed out on the Computer/Internet Issues corrected me 'voice over Internet' I believe I could comfortably make calls (God forbid over my laptop mike/speakers rather than headset) as soon as the already approved internet facilities become more common.
Banning the mobiles might reduce but won't stop the halfwits (or very busy business folks like wot I is).
18th Dec 2004, 06:36
the airlines should separate those who want to use their phones behind a partition.
Yea, the rear bulkhead. :mad:
18th Dec 2004, 09:53
Only about 15% of passengers will use their mobile phone onboard an aircraft for business reasons. The other 85% will just think of it as a novelty and phone someone just to say they are using their mobile phone on an aircraft. So therefore, as Loose Rivets said, I also reckon that “mobile phone class” should be located at the rear away from everyone else.
18th Dec 2004, 10:11
18th Dec 2004, 15:16
Agree with you 100% - but isn't there anywhere further back than the bulkhead that these poor sad, insecure people could be put???!!!
18th Dec 2004, 15:18
re. 2R's question about the interference problem.
A cellphone adapts its transmission power according to the quality & strength of the connection to the ground station. Currently a cellphone must try to connect to a ground based station even when in the air. The distance to what is designed to be a short range service means the cellphone must use its maximum transmission power to try to connect - especially since it's trying to get through all that metal in the fuselage surrounding the antenna. When no signal from a ground station is received the phone continues to broadcast at max. strength until a connection is made. As signal strength improves a cellphone reduces its transmission power.
NB: I think a phone can also be instructed by a ground station to reduce its power output.
The systems that are being examined on a/c involve the use of a 'picocell' on board the a/c ie one where a very low power 'ground station' is mounted on the a/c. This station can then provide a good quality connection to the phones - which means a much reduced transmission power from each of the phones, possibly even forcing the phones to reduce their output.
In addition, the picocell is/will be a certified bit of equipment, designed & installed not to interfere. It will use an external antenna system to connect to the outside world, just like the current radio systems do, so avoiding the Faraday cage effect of being inside the fuselage.
The picocell's connection to the ground services will be via a dedicated link designed for the task (satellite), not the cellular antenna system, so that avoids swamping & hand-off problems for the cellular network.
18th Dec 2004, 19:22
playing with VoIP (Voice over IP) - or as one of our more technolgy orientated members pointed out on the Computer/Internet Issues corrected me 'voice over Internet' I Not sure what the other person is saying here.
VOIP is a method of transmitting Voice using the Internet Protocol. The protocol may not be used across the internet, it can be used within a building (for example) but it IS Voice over I.P. not over the internet.
PAXboy deselects pedant mode but in his defence, points out that he has been in telecomms for over 25 years. :ooh:
"I tell you, we are here on Earth to fart around, and don't let anybody tell you any different." Kurt Vonnegut, Jr.
OK I can do pedant as well as anyone else !!
Posh VoIP involves internet tunneling (and as you appreciate PAXboy this comes in many different flavours) or private networks (both of which guarantee bandwidth and latency).
Poor boy's VoIP involvs exactly the same comms protocol across public internet access and, in theory, can take a week to reach its target (a touch of lag) as there are no bandwidth/latency guarantees.
Whichever, I can be an absolute 'pain in the arse' as soon as internet acces onboard arrives rather than waiting for mobile phone access.
18th Dec 2004, 22:43
Regardless of what happens aboard flying busses, I understand mobile use was banned on private flights also, due to interogating too many ground stations at once.
If that's a furphy then there is no reason why I can't use a phone while flying my Cozy. What happens aboard the smoke-belching airliner above is SEP.
19th Dec 2004, 00:57
Isn't it surprising that the technology described by Tinstaafl is available for chatter, when people can spend many man-days looking for the ‘black box' after an accident. When will we have instant telemetry sent to a satellite to avoid this?
19th Dec 2004, 23:34
But you can get telemetry transmitted from the aircraft. As well as weather report and everything else.
The secret to this is to get the punters down back to fork over 20 or 30 dollars for the connection per flight. This pays for the equipment and the big satellite pipe to carry it all up and down to the ground station and into the Internet. Telemetry and the other stuff for running the flight tales up very little bandwidth and is a freebee, while the airline finds another profit center. Goodness knows they need some.
Next it will be yacking/non-yacking sections; child /non-child; peanut/non-peanut; etc the possibilities are endless for the creative.
21st Dec 2004, 19:43
To the business types all I would say is what did we do before mobile phones were common?
The good old fashioned message service or the secretary.
I used to think that the mobile was a useful tool. Now if you haven't got one people treat you like the missing link.
6th Jan 2005, 17:22
Total Hell! Mobile 'phone class, constant Trisha/Jerry Springer on the IFE, special in-flight magazine features on best shell suit, text message typing competitions...maybe not. But just watch air rage incidents rise when people get fed up listening to mobile 'phone conversations. Bad enough on trains, never mind longhaul.
9th Jan 2005, 09:04
Currently a cellphone must try to connect to a ground based station even when in the air. The distance to what is designed to be a short range service means the cellphone must use its maximum transmission power to try to connect - especially since it's trying to get through all that metal in the fuselage surrounding the antenna. When no signal from a ground station is received the phone continues to broadcast at max. strength until a connection is made.
Rubbish. Do a search and you can find out how it really works.
However mobiles on aircraft should remain banned. Would annoy the ar$e off most people.
9th Jan 2005, 12:16
Vortex - would you be kind enough to post a specific link to a relevant post: A search on this subject reveals that there are nearly as many opinions as to how cellphones may/may not interfere as there are people posting on the subject.
Tinstaafl's post certainly appears (to the technically inept like me) to be a reasonable explanation, and one that I have used, in a simpler version when dealing with customers - If it is proven incorrect, then I'd be pleased to get the correct facts instead.
10th Jan 2005, 01:56
Previous post is a bit abrupt :\ but it was late.....A precis of some past posts I have made on the subject:
Cell phones do NOT always TX. There is an idle mode, which is when you are not making a call and this does not require the phone to TX. It searches for base stations by listening and measuring the received signal. It only transmits (and not always at full power) when it is first turned on to register itself on the network or when it moves from one LAC (local area code) area to another. This is a problem as you will be sure to pass between several of these while flying causing a transmission to be made for about 6 or 8 seconds each time. There is also a Location update, which is set on a timer specified by the network which can be several hours, which sends the same information every update (again it only last for 6 to 8 seconds). This is the “dit diddle lit dit” type sounds you hear over your radio or TV from time to time when your mobile is close to it.
For all that a class 4 cell phone (which is what most modern phones are) have a power output of only 0.2 to 2 watts (haven’t checked this and my memory is not perfect but it is not far out). This is a very small amount of RF energy. That being said there have been cases mentioned earlier, where even this has proven enough to cause problems. The rule stipulating no phones on during the whole flight is a reasonable safety net to prevent accidents. Besides, as was mentioned earlier someone can still call in and it will then carry out a lot of signaling and if accepted then into dedicated mode, which is when it starts transmitting all the time.
For those interested most calls made in a jet would fail anyway, as GSM (or CDMA for the Americans and some Asians) is not designed to work above 300KPH for many many technical reasons. Not least of which it does not have time to hand over the call between cells fast enough.
Original thread can be found here (http://www.pprune.org/forums/showthread.php?threadid=66460)
Of course if you are making a call the phone IS transmitting and can be using full power if it is required to maintain the call. The mobile can change its power everytime a status report is sent to the BSC (Base Station Controller), which is about every 5 seconds.
I could go into the myriad of issues with mobiles but I think that covers it in a nutshell with regards to aviation.
Just to qualify these comments I'm an RF engineer working for one of the worlds largest mobile operators. I've been working in telecoms for over 20 years and GSM/CDMA/3g... for the last 7.:ok:
10th Jan 2005, 07:54
10th Jan 2005, 11:50
So, as I understand it, you have dozens of mobiles on a flight all merrily communicating via an on-board 3G picocell, which then relays via satellite comms. My question is, what happens if (when) the picocell fails - won't all these phones start 'shouting' in an effort to contact the nearest base station (on the ground)? If that isn't a scenario likely to cause interference with avionics, why all the concern about the use of mobiles on flights over the past few years?
10th Jan 2005, 12:28
Vortex did a good job of explaining things, may add a little.
A mobile will only transmit when it has successfully decoded a broadcast from a cell. If it can "see" several cells on the same frequency it will be unable to decode any of them. So the old wives tale that it will transmit and confuse a large section of the network is untrue. It is the reception from multiple cells that confuses the mobile, into silience.
With regards using a mobile on a A/C the problem isn't in the cruise as for various reason mobile phones are unlikely to make contact with a ground based basestation. However as the A/C desends there comes a point when the phone manages to decode a cell it then transmits to register with the network. Lots of mobile phones could be doing this at about the same time, creating quite a bust of RF activity. Of course once registered the mobile is likely to receive text messages, voice mail notifications and possibly incoming calls.
With regards to the loss of an on board picocell the phone won’t start transmitting it will start listening, scanning all channels looking for a cell. Only when one is found will it make a limited number of attempts to make contact.
Could go on and on, but I see you’re bored already