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So, what does the G in GPS *really* stand for?
- Thread starter wrboyce
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To save some money I downgraded my GPS to HPS .. Hoe Positioning System. Even though it wont tell me exactly where the gangstas are...at least I know I 'm in the general vicinity. Occasionally though, when AT&T's network is acting up , it'll take me to all the hardware stores... I can't figure it out. Maybe its defective.
If you move to a substantially different position it can take GPS as long as 15 minutes to figure out where you are without giving it a hint of roughly where you are. The Wifi and cell tower triangulation is supposed to help with this, but if it isn't it may have just needed more time to detect which satellites it saw and calculate what location could possibly have the various combinations of satellites seen.
UK to Spain doesn't sound that radical, but I've gone from Boston to San Francisco and if I hadn't told my GPS (not an iPhone) that I was now on the west coast it may have taken longer than my drive from the airpot to my hotel to figure out where I was. Does the iPhone have a feature where you can give it a hint of roughly where you are? Something more than the Skyhook system that was used on the first gen iPhone and touch.
+1
When the OP said he left it out for up to 10 minutes, that could easily have been only about half the period required to latch onto the four satellites often needed to determine x,y,z and exact time.
I have had issues with the GPS in every country I have taken the phone. I find even if I pre-cache the maps in the area I cannot get a gps location without enabling data roaming. I always get the "cannot find your location" message at first, so I enable data roaming, open maps, close maps, disable data roaming and then it all works (apart from new data download).
It seems the iphone needs data access for a few seconds to enable/authorise gps use? Wifi access also works for this.
It seems the iphone needs data access for a few seconds to enable/authorise gps use? Wifi access also works for this.
You need about 12 solid minutes to update the ephemeris and almanac tables.
GPS can track as you move through the satellite net.
At point A you device knows satellites 1-9 are withing line of sight (that part of the net)
When you move say 500 miles with the device receiving any signals, when the device is powered up it is stil trying to look for satellites 1-9. When no satellites are found it searches for other satellites to update the almanac data. this can take a while.
Ephemeris data is the health and positin of the individual satellite
Almanac data is the info of where the satellites are.
I had the same problem (UK to Spain) and I think I know what happened.
According to this article, the GPS on the iPhone is assisted. Which means it uses WiFi and data to find a position first. When you go abroad, if you turn off data roaming for obvious reasons, you should use a WiFi connection to try to help it know where you are. If you don't have a Wifi signal you need to leave the iPhone 5-15 minutes to find the GPS signals. But most apps will time out if they can't find a GPS signal fast enough so you need an app that will doesn't time out, let it search for 5-15 minutes, and then after that it should be able to find on other apps using just GPS (the article suggests G-Spot).
I haven't tested this out yet, and don't know which apps don't have the time-out on GPS, but maybe someone who is going abroad can let us know.
According to this article, the GPS on the iPhone is assisted. Which means it uses WiFi and data to find a position first. When you go abroad, if you turn off data roaming for obvious reasons, you should use a WiFi connection to try to help it know where you are. If you don't have a Wifi signal you need to leave the iPhone 5-15 minutes to find the GPS signals. But most apps will time out if they can't find a GPS signal fast enough so you need an app that will doesn't time out, let it search for 5-15 minutes, and then after that it should be able to find on other apps using just GPS (the article suggests G-Spot).
I haven't tested this out yet, and don't know which apps don't have the time-out on GPS, but maybe someone who is going abroad can let us know.
when GPS doesn't find you, reboot your iphone.
it's happened a couple of time to me. Then you're found almost immediately.
it's happened a couple of time to me. Then you're found almost immediately.
Last easter I jumped on a plane in Spain, and arrived in Iceland, that's about 4220 miles, and my iphone's gps took about 10 seconds to find me.
Just an fyi, I'm pretty sure Movistar has the iPhone. I'm moving to Spain next year so I checked out the iPhone carrier prices a few months ago.
And how'd you manage the scratch?
To answer the OP's question I would suggest from the above that it is Geek Provides Statistics.
ahahahahahahahahahahahahahahahahahah.
ahem. Sorry kdarling couldn't resist