GPS is wrong

[boogi]

I know this isn't a huge issue, but I was just curious about the GPS functionality on the iPhone 3G. Whenever I'm at home (in a large metropolitan area) and use the locate function on Google Maps, it places me 10 blocks north of where I actually am. It does this every single time, even though it's pretty good about locating me in other areas of the city.

What could be causing the tracking to be off every single time? Do you think this is something that can/will be fixed either through software or with more cell towers eventually installed in the area? Thanks!

 

[kilsey]

I know this isn't a huge issue, but I was just curious about the GPS functionality on the iPhone 3G. Whenever I'm at home (in a large metropolitan area) and use the locate function on Google Maps, it places me 10 blocks north of where I actually am. It does this every single time, even though it's pretty good about locating me in other areas of the city.

What could be causing the tracking to be off every single time? Do you think this is something that can/will be fixed either through software or with more cell towers eventually installed in the area? Thanks!

Stupid question, but are you indoors when you're trying this? Just wondering if it's a matter of cell tower vs. actual satellite. Also if it's a city with skyscrapers, an accurate fix may be harder to come by.

 

[supermum]

Are you using WiFi on your iPhone when this is happening. If so, turn WiFi off and see if you have different results. Just a suggestion to see if it changes anything.

 

[boogi]

Stupid question, but are you indoors when you're trying this? Just wondering if it's a matter of cell tower vs. actual satellite. Also if it's a city with skyscrapers, an accurate fix may be harder to come by.

I am indoors (but right by the window). I suppose that it probably can't pick up a GPS signal and relies on the cell towers, which place me 10 blocks away. Again, not the biggest deal in the world, I was just curious.

Also, I tried turning wifi off and it it locates me within a 50-block radius, so the results are different... and worse. Thanks for the suggestions though.

 

[kilsey]

I am indoors (but right by the window). I suppose that it probably can't pick up a GPS signal and relies on the cell towers, which place me 10 blocks away. Again, not the biggest deal in the world, I was just curious.

Also, I tried turning wifi off and it it locates me within a 50-block radius, so the results are different... and worse. Thanks for the suggestions though.

Ah, ok. You need 5+ of the satellites to get a really accurate fix (at least 3 for a decent one within a block), so it's probably relying on cell tower and wifi for location. I guess the good news is that you know exactly where to go for 5 bars of reception - 10 blocks away

Weird that the fix degraded so much with Wifi turned off - I wouldn't have expected that.

Out of curiosity, can you try getting a fix while standing outside your house/building? How accurate is that?

I've ridden on a commuter train and watched the little blue dot version of myself pull into the station on Google Maps...