Sidebar Sidebar
Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

Weird GPS Bug/Problem

B

bengtc

macrumors regular
Original poster
Oct 29, 2008
245
12
When I am inside a building and my I4 is using triangulation to find my location it gives me a location not even near me. The weird thing is it keeps saying I am in St. Paul, MN (for the Map, Flixter, Weather channel app) even though I am about 60 miles north of St. Paul when I am at home or 30 miles north when I am at work. No matter where I go if I cant get a gps signal the current location I am given defaults to St. Paul MN.

Another note:
-When I turn off 3g it will give me a location about 50 miles SE of my home. Whether I am at work or at home it will give me this fixed position.
-It seems to be whenever I cannot get a definite gps signal the location I am given is a fixed location no matter where I actually am located.
 
do you want to ask a question? perhaps you should re calibrate your GPS by doing the "figure eight thingy" with your phone...and put auto lock on NEVER
 
ivan300 said:
GPS needs a direct line of sight to the sky otherwise it can not get signal

</Thread>
Click to expand...

It's a good thing you cut off "and my I4 is using triangulation" in the part you quoted. Because if you'd left that in there then it would have made your comment seem pretty pointless.
 
Small White Car said:
It's a good thing you cut off "and my I4 is using triangulation" in the part you quoted. Because if you'd left that in there then it would have made your comment seem pretty pointless.
Click to expand...

How so? His thread is called "Weird GPS Bug/Problem". I explained why GPS doesn't work.

Cellphone tower triangulation is not supposed to be accurate. Some times it can be accurate from 60m to 1.5km.
 
Maybe I shouldnt have put GPS in the title but the weird thing is why, no matter where I am (home or work 30 miles difference) the cellular triangulation location gives me the exact same address. When I turn 3g off it gives me the exact same address in both cases but in a different city.
It also just recently started doing this. Never had a problem before when opening Flixter and seeing theaters around me when in my house, and now it shows me theaters about 60 miles away when I open the app in my house.
 
-aggie- said:
No, it can still get a signal indoors. It’s just a weaker signal. FYI, I have a pulsing blue circle at my location inside my house at the moment.
Click to expand...

Download "GPS Info!" from the app store. It will tell you the locating method. I guarantee while your inside it will be "cellular"
 
ivan300 said:
Download "GPS Info!" from the app store. It will tell you the locating method. I guarantee while your inside it will be "cellular"
Click to expand...

Wrong. It initially said Cellular, but then changed to GPS in about 30 seconds (like it should, since the cell triangulates, so it can find the satellite, if available). Next.
 
Whenever I am using triangulation my location is the same spot no matter my actual real location. I have tested in 3 different cites about 45 miles apart.
 
bengtc said:
Whenever I am using triangulation my location is the same spot no matter my actual real location. I have tested in 3 different cites about 45 miles apart.
Click to expand...

Have you restored your phone and setup as new. It sounds like your 3G/EDGE coordinates for towers are wrong. Also, if you use wifi, what do you get?

The next thing you might try is to go outside and reset your network settings and turn off and then turn on GPS.
 
^^ I get the same incorrect location when using wifi, I really want to wait to restore to a new phone as a last resort. I'll try resetting network settings and see what happens. Thanks!
 
OP, is your WiFi is turned off, so you're actually using Cell Id locating?

Quick lesson in cell id for everyone:

1) AFAIK, it doesn't do any triangulation (or more accurately, trilateration). It was an excited verbal mistake that started that myth. I don't think that has changed.

2) It's not based off coordinates of cell towers either.

3) It IS based on a database (originally Google's, now Apple's since OS 3.2) of GPS user locations + their current cell sector id, which have been collected in the background by phones and sent up to the respective mothership.

Each cell usually transmits out in three sectors, each with its own id. Over time, as GPS coordinates of users using each sector is collected, a virtual center of that sector can be calculated. That is what is returned to the phone app when it's using cellular locating.

Using a sector is more accurate than just using the tower's core cell id.

Sometimes cell ids are swapped or reused by a carrier, and this confuses the heck out of things for a while. I believe not long ago this happened between southern California and Boulder CO.

It's possible that Apple's database has a glitch. OP, the only way to tell if it's that or your phone, is for someone else with an iPhone to try in your same location(s). But certainly try the restore first.
 
You must log in or register to reply here.
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.
Top Bottom
Back