AirTalk.org Aviation discussions newsgroups   Archives   FAQ   Search   Memberlist   Usergroups   Register   Profile   Log in to check your private messages   Log in  Cell phones in gliders - tracking function          AirTalk.org Forum Index -> Sailplanes View previous topic :: View next topic   Author Message Bill Daniels Guest Posted: Sat May 05, 2007 8:18 pm    Post subject: Cell phones in gliders - tracking function It's probably no surprise to anyone that cell phones can be tracked even when they are not being used in a call. You can Google "Cell Phone Tracking" and get enough information for a long evenings reading. My carrier, Verizon, offers "VZ Navigator" a $10/mo service which enables my GPS equipped cellphone to automatically send SMS messages with location data to another cell phone every few minutes. If the receiving phone is equipped with the same service, the location data is displayed on a moving map. It's described as a way for parents to keep track of children. The main news concerns privacy issues but the service can be turned on and off by the user. Third party services offer to put location data on the internet so anyone with access can see the location real-time. It's not hard to imagine practical uses for locating a glider pilot (or his crew) during and after a flight. For example, if a pilot enables this service, his crew could track the flight real-time. It appears that it works anywhere SMS messaging works. Bill Daniels Back to top Tuno Guest Posted: Sat May 05, 2007 8:33 pm    Post subject: Re: Cell phones in gliders - tracking function I'm a Verizon customer, and the only place I've been able to get my phone to work in a glider above pattern altitude is in areas where SMS does not work. Maybe that will change someday ... -ted/2NO Back to top Mal Guest Posted: Sat May 05, 2007 8:39 pm    Post subject: Re: Cell phones in gliders - tracking function "Tuno" <tedcwagner (AT) gmail (DOT) com> wrote in message news:1178379229.514688.270100 (AT) y80g2000hsf (DOT) googlegroups.com... Quote: I'm a Verizon customer, and the only place I've been able to get my phone to work in a glider above pattern altitude is in areas where SMS does not work. Maybe that will change someday ... -ted/2NO Does the GPRS work at altitude. http://www.silentwings.no/article/articleview/106/1/1// Back to top Tuno Guest Posted: Sat May 05, 2007 8:57 pm    Post subject: Re: Cell phones in gliders - tracking function Quote: Does the GPRS work at altitude. Nope. Back to top Tuno Guest Posted: Sat May 05, 2007 9:19 pm    Post subject: Re: Cell phones in gliders - tracking function If I recall correctly from my base station programming days, GPRS is the bearer channel for SMS, so if SMS isn't working, it will almost certainly be because a GPRS channel cannot be opened. I think Verizon's GPRS only works in areas where it can be executed with lower power consumption, which means being close to the ground radios. I'm very curious whether other service providers can do SMS at altitude (or any other packet-switched service). Back to top rustynuts Guest Posted: Sat May 05, 2007 9:32 pm    Post subject: Re: Cell phones in gliders - tracking function My GPS tracking phones I use to track my small fleet of trucks do not show altitude. They only show location and speed and you can overlay tracking on a map (on the web). Last weekend my track from Cal City to Mt. Whittney and back to WJF & L71 showed up quite nice. The phone receives GPS and every 15 min it sends via a cell call to a server the phone position stored every 5 minutes. I can ping the phone and get on demand location & speed if the phone can contact the cell site. If the cell phone cannot contact a cell site it will store until it does and than down load all stored points. If I had of landed out in the Sierras it probably would do me no good except to show last position tansmitted maybe in the air? If in the Valley it could come in handy if incompasitated. Back to top Bill Daniels Guest Posted: Sat May 05, 2007 9:36 pm    Post subject: Re: Cell phones in gliders - tracking function I've had pretty good luck in remote areas while airborne. Apparently, SMS works when voice calls are not possible. But then, in Colorado, cell towers are located on mountain peaks. As I understand it, if SMS service is not avaliable, the 'phone will hold the message until it is and then send it. The message gets through even if not in real-time. The only way to know if tracking works is to try it. Bill Daniels "Tuno" <tedcwagner (AT) gmail (DOT) com> wrote in message news:1178379229.514688.270100 (AT) y80g2000hsf (DOT) googlegroups.com... Quote: I'm a Verizon customer, and the only place I've been able to get my phone to work in a glider above pattern altitude is in areas where SMS does not work. Maybe that will change someday ... -ted/2NO Back to top Gary Emerson Guest Posted: Sun May 06, 2007 5:24 pm    Post subject: Re: Cell phones in gliders - tracking function Bill Daniels wrote: Quote: It's probably no surprise to anyone that cell phones can be tracked even when they are not being used in a call. You can Google "Cell Phone Tracking" and get enough information for a long evenings reading. This handy application will let you locate just by entering a phone number. Give it a try... http://www.sat-gps-locate.com/ Back to top Guest Posted: Fri May 11, 2007 2:14 am    Post subject: Re: Cell phones in gliders - tracking function On May 8, 3:47 am, Iwo Mergler <Iwo.Merg...@soton.sc.philips.com> wrote: Quote: Mal wrote: "Tuno" <tedcwag...@gmail.com> wrote in message news:1178379229.514688.270100 (AT) y80g2000hsf (DOT) googlegroups.com... I'm a Verizon customer, and the only place I've been able to get my phone to work in a glider above pattern altitude is in areas where SMS does not work. Maybe that will change someday ... -ted/2NO Does the GPRS work at altitude. Here is a simple overview of the factors for marginal GSM coverage. I hope it's useful and not too boring. Wether or not you'll get a signal depends mostly on the basestation antenna radiation pattern. The operators normally use directional antennas, covering the ground of the cell only. Some of that gets reflected upwards, but that coverage is patchy. There are of course situations where a basestation has been pointed skywards (e.g. illuminating the side of a mountain), so in some rare parts of the sky GSM works well. Now, SMS uses the GSM control channel, the one which is also used to establish a call. This channel has a very simple protocol, very much like humans do radio communication - listen and if nobody else talks, talk. It only takes a small patch of coverage for an SMS to get through. Also, as others have pointed out, the phone will hold a SMS until it finds such a patch. For a phone call proper, you need essentially uninterrupted coverage for the duration of the call. In principle, if an SMS can get through you can start a call, but it could be extremely short. GPRS is a data transfer protocol which uses the spare channel capacity, anything which is not used for calls. Since it's a packet based protocol (each like very large SMS), it has a slightly better chance of "getting through" than a phone call. However, since the packets are larger, the patch of coverage must last longer. Also, the system will only retry for a few seconds before giving up. SMS will retry all week is it has to. Among other things, GPRS is used to transfer the bulk of data for MMS (pictures, video clips, etc.). Iwo they need to add an altitude feature and get it FAI approved. of course then they'd probably charge 800 bucks for the phone Back to top Roger Worden Guest Posted: Sun May 13, 2007 6:13 am    Post subject: Re: Cell phones in gliders - tracking function Now that's really funny! "Gary Emerson" <emerson_gary (AT) sbcglobal (DOT) net> wrote in message news:uNj%h.291$sL7.252 (AT) nlpi061 (DOT) nbdc.sbc.com... Quote: Bill Daniels wrote: It's probably no surprise to anyone that cell phones can be tracked even when they are not being used in a call. You can Google "Cell Phone Tracking" and get enough information for a long evenings reading. This handy application will let you locate just by entering a phone number. Give it a try... http://www.sat-gps-locate.com/ Back to top Display posts from previous: All Posts1 Day7 Days2 Weeks1 Month3 Months6 Months1 Year Oldest FirstNewest First         AirTalk.org Forum Index -> Sailplanes All times are GMT Page 1 of 1   Jump to: Select a forum Aviation----------------alt.aviationAviation safety EnhancementPlanes, gliders and flying in AustraliaAviation et pilotage (Français)rec.aviationAviation (Aerobatics)Hot air, gas balloons and airshipsHang-gliding, paragliding, foot-launched flightAircraft Design & BuildingInstrument Flight RulesAviation (Classifieds)Military AircraftNaval AviationAviation (Miscellaneous Topics)Owning AirplanesAviators (General Discussions)Aviation related productsAircraft RestorationHelicopters and rotary wing aircraftsFlight SimulationSailplanesAviation (Students)Light aircraftFlying related activities in the UK Airports----------------alt.airportsEdinburgh Airport Glasgow Airport Humberside Airport Luton Airport Aberdeen Airport Glasgow Prestwick Airport  You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum Powered by phpBB © 2001, 2006 phpBB Group SEO toolkit © 2004-2006 webmedic.