ehm, what? Assisted GPS ist NOT as accurate? Not as accurate as what? GPS? Hello? A-GPS is GPS PLUS assistance from cell towers. It is BETTER then just GPS.
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International 4G iPad Models Will Work on AT&T, Not on LTE in Home Countries
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Why can't these stupid telecommunication companies talk to each other and have a standard frequency for LTE. This was the perfect time for all these companies in different countries to agree on a standard, instead they created the same mess like on the 2G and 3G, everybody has a different frequency.
It's not the telcos fault, they buy whatever frequency they can, which most governments auction off
A-GPS is ONLY assistance from cell towers (and surrounding wifi hotspots). No network, no GPS.
Or have I missed some vital information here? Is there any way I can use GPS on my iOS devices with 3G and WiFi disabled?
You forget to mention, that Vodafones rural coverage is stationary, meaning its used to give clients a fast internet line because there is no DSL available. Not to be used with mobile devices. Not even possible to use with mobile devices. You get a USB stick but when you move outside your "home zone" you got no more coverage. Not really what you want with an iPad (or any other Pad for that matter)
The networks that are for mobile devices (ig in the Collogne aerea) have ALWAYS a fallback to UMTS 3G because they could not use voice otherwise. Tests have shown, that the real world download speeds are faster on 3G then on LTE, they only cost more on LTE.
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You did miss something there:
http://en.wikipedia.org/wiki/Assisted_GPS
And yes, you can use your GPS without 3G (even without SIM) and without Wifi. Only drawback is that it can take up to 10 mins for a fix from a cold start and you have to have a really clear view of the sky, outside only.
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Hmmmmm if you have no wifi or 3G it takes longer to acquire lock. No its not better. It's used in phones cause it saves battery and it can lock on faster if there is 3G or wifi.
http://www.gpsreview.net/a-gps/
It has it's pros and cons.
Yes, thats exacly what I said? GPS alone takes up to 10 mins from a cold start. Thats where the "A" for assisted comes in that makes the a-gps better. It locks on faster and is more acurate. So how can you say its not better? If you do not like the assist, you can use the GPS alone. That takes longer and is not as accurate.
The post I answered stated that a-GPS has no real GPS build in, that is wrong. A-GPS has a regular Satellite receiver build in (behind the plastic strip on the back of the iPad 3G/4G)
Ill keep it simple.
A-GPS as used in mobile device has weaker strength to conserve batter life. If is will not peak up weak signals like a dedicated GPS in a Garmin or tomtom which sucks though batteries.
If you go in areas where you loose wifi/3g and there are weak signals it starts to **** itself. A dedicated GPS like a garmin/tomtom will pick up weak signals.
For the sake of battery saving, its not AS POWERFUL as a dedicated gps.
Every used a tomtom/garmin on a battery? They have big batteries and yet they chew through them damn fast. There is a reason... strength.
10min? what dedicated GPS do you have?
go for a drive in build up area with tall buildings ie... london and where you 3g goes off.... GPS starts loosing itself on the iphone.
If you cannot get lock, you use accuracy. Quiet simple.
A-Gps is a great compromise for mobile devices. And no its not as good as a dedicated GPS as used in garmin/tomtom devices. If you go somewhere really desolate, bring a dedicated GPS..... you ipad will loose lock depending on where you are.
If I'm looking at that map correctly, it's only in rural areas. In other words, if I'm in Munich, all I get is 3G. If I go about 40 miles outside the city, I'll get LTE. So I doubt that "82 million people" are covered by LTE in Germany.
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That sounds a lot like the controversial Verizon HomeFusion service for rural areas.
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lets say i buy a new ipad with 4G in the US, if I travel to Europe or South America, can I buy a sim card for a country and use it there as i would in the US?
lets say i buy a new ipad with 4G in the US, if I travel to Europe or South America, can I buy a sim card for a country and use it there as i would in the US?
So what you are saying, in a REALLY desolated aerea(mountain valley in the Himalayas?) without 3G coverage a phone or iPad looses signal?
Well, I guess that is of little to no concern to most.
In a build up area if you loose 3G, eg you are underground or inside a building, your dedicated GPS will not be any help either. They loose connection already in a short tunnel.
The worst I could throw at my iPad until now where hiking in the rockys and a documentary on Madagaskar, both places have no 3G, Wifi or indeed 2G coverage, but my GPS Kit on the iPad worked a charm. The also available Garmin was also working but with the tiny screen and EXTREEMLY limited Battery life before lunch rather useless.
My 10 mins from cold (without assist) was ment to be the iPad. The Garmin Trecker is in 3 mins up and ready with a good clear view of the sky for the first 4 Satellite lock.
Out in the dessert, the mountains or similar, you simply do not have weak signals, you would be amaised how good reception is, even on the iPhone. On my iPad I cross the single lane street in front of my house, the iPad will show that on google earth, down to the fact if I'm still on the sidewalk or already on the grass, the garmin does not even budge.
As I understand the situation, if you buy the AT&T 4g vesion, you should be able to come to Europe, purchase the sim card, and have a the same or better performance compared to the ipad2. If someone disagree, please say so.
Yes, you can use a local SIM and you will get access to high-speed 3G in most of Europe that is as fast or faster in real world use as our LTE is here.
This will also work with the Verizon version.
A real GPS shows your location with under 1 meter accuracy and shows your speed at 1km/h accuracy.
Assisted GPS is for cheap crappy GPS chipsets which cannot get the signals straight from the satellites.
Do you think that airplanes and ships use also, these cell tower assisted GPS things?
No, they dont. Because they have decent GPS chips on their navigation devices, just like any TomTom GPS navigation solution to your cars. Cars dont use cell tover assisted GPS either. Only crappy mobile GPS chips have to use that stuff.
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And for a reminder there is no stinking data or tethering limits here in Europe either. Some operators use them, but there is plenty of operators who wont limit your 3G/4G data at all.
I can download 5 terabytes of data with my mobile, with no extra charge. That it how it should be and that is how it will be here.
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iPad 4G LTE connections wont work in Europe.
http://www.cultofmac.com/150802/ipa...d-verizon-but-only-3g-internationally-report/
The actual accuracy has nothing to do with assisted or not. When I go outside and use only the gps on the iPad (no assist) I receive 8 satellites, my garmin dedicated(and expensive) GPS receives.....8 satellites. Accuracy with both, 1-3m. The Garmin is much slower, when I start moving, it takes up to a minute to react, the iPad moves in real time.A real GPS shows your location with under 1 meter accuracy and shows your speed at 1km/h accuracy.
Assisted GPS is for cheap crappy GPS chipsets which cannot get the signals straight from the satellites.
Do you think that airplanes and ships use also, these cell tower assisted GPS things?
No, they dont. Because they have decent GPS chips on their navigation devices, just like any TomTom GPS navigation solution to your cars. Cars dont use cell tover assisted GPS either. Only crappy mobile GPS chips have to use that stuff.
And yes, the Tom Tom in my car got assisted GPS, of course, it also receives Information in real time about traffic around me, how else would I know a detour because there is a traffic jam ahaed?
And yes, Airplanes do use assist, every little bit of help is welcome since it narrows the error margin. They not only use cell towers, but airport fires as well.
Back in 2005 I had Nokia 9300 communicator and separate Bluetooth GPS receiver. It was 100% accurate with 16 satellite connections and the battery on that tiny thing lasted about 20hrs
The Navicon GPS software worked flawlessy with Nokia 9300's 150mhz ARM cpu.
And that was 7 years ago.... pfff
I though NTT DoCoMo was one of the few carriers to support LTE on the 2100 MHz band?
Funny. The wifi-only ones in the USA don't have LTE at all. Yours must be different. Or is wifi different there, too?
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You understand that aGPS adds, it does not subtract. My phone is more accurate with location than my dedicated GPS. Mainly because it is faster to lock on.
Touche. But so did the US Navy
Read the thread, profet. LTE is all over Europe. And buying Apple products without looking at the tech specs, is like buying a BigMac for the low fat content.profets said:
Touche. But so did the US Navy
Read the thread, profet. LTE is all over Europe. And buying Apple products without looking at the tech specs, is like buying a BigMac for the low fat content.
What the heck are you talking about? Making up quotes with my name?
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Guys, Europe is a land where you are LUCKY to get 3G service. As someone who's traveled a lot, I can tell you that despite the myths and rumors, mobile phone service in the US blows Europe out of the water. However, our prices are much higher in the US. And "Europe" is a continent, not a country. And the US is large enough it needs to be looked at state-by-state. Mobile service in Ireland, for example, is generally fantastic. In the UK and Germany - it's atrocious.
Same in the US. Some states are great. Others (Kansas... we're looking at you) are awful.
Same in the US. Some states are great. Others (Kansas... we're looking at you) are awful.
xinu, assisted GPS is completely "real" - what the assisted part means is the cellular data network provides almanac and ephemeris data to the GPS receiver. This is much faster than waiting for this data to be broadcast (a "cold fix" in GPS receiver terms) and allows a position fix to be attained much more quickly. It has nothing to do with the quality or accuracy of the fix, and most a-GPS implementations function fine in standalone mode if necessary. All the assistance does is dramatically reduce time-to-first-fix.
Oh, and civilian GPS isn't anywhere close to 1 metre accuracy on it's own (military GPS runs on two frequencies allowing complex ionospheric correction math to be done in the receiver increasing accuracy). When you see 1m fix accuracy (which actually is 1m with 95% confidence - there's still a 5% chance you're off by more than 1m) on a GPS receiver, additional assistance beyond civillian GPS is being used.
WAAS (Wide-Area Augmentation System) is the most common such assistance. It is an FAA system using two geostationary satellite to broadcast ionospheric correction data from known ground stations. This system is most useful the closer you are to a ground reference station, but always increases accuracy both by providing this correction data, and also by being two additional satellites to use in calculating a fix. Generically, this is a SBAS (Satellite-Based Augmentation System), and Europe has their own and other countries are developing such systems.
An older system called DGPS (differential GPS) is provided by the US Coast Guard (in the US) and provides similar data from land beacons. Few receivers currently use this system, though it was common in the days of SA (Selective Availability - the deliberate error once added to the civillian use GPS signal). DGPS is more expensive to implement (and WAAS was not available), has lower availability, but was absolutely essential to useful position fixes in the days of SA.
Finally, some modern GPS receivers make use of GLONASS. GLONASS is a very similar system to GPS, developed by the Russian government. It was allowed to degrade after the collapse of the USSR, and finally completely re-launched last October. Except at high latitudes, it provides no real benefit over GPS, however, it provides MORE satellite, more data, and a more accurate fix when combined with GPS. The greatest improvement is in areas such as urban canyons where the video of the sky is restricted. Given the high accuracy GPS alone provides, along with GPS' proven track record of availability, and the accuracy possibly with WAAS, there would be little incentive for manufacturers to quickly add GLONASS support to their product lines. Seeing this, the Russian government has a duty on all GPS navigation devices - that is waived if they support GLONASS. Given that GLONASS further enhances position accuracy and availability, there's no real reason NOT to add it to all devices world wide (possibly battery life). Expect most GPS receivers to support GLONASS within a couple years. Many, such as the new Garmin eTrex models, and the Qualcomm chipset used in the iPhone 4S and many Android phones, already support GLONASS.
Seeing this, do you still want to say assisted GPS isn't "real"? The GPS performance on my iPhone 4S will generally be better than the GPS performance of my old Garmin eTrex Vista. Almost instant time-to-first-fix thanks to assistance data. GLONASS support to provide approximately double the available satellites for a fix in low-signal areas. The Garmin's advantage, of course, is WAAS. Which gives it higher accuracy out in the open since it's able to correct for atmospheric errors. Either one is a highly accurate, modern GNSS (generic name for GPS, GLONASS, and similar systems) solution. I just wish Apple allowed developers to access the details of the GNSS status (how many satellites it sees, is using for the fix, detailed fix accuracy, etc). How I wish I could have an app that just gave me the technical GNSS data. Dang app store...
Now, if you want to see a BAD GNSS implementation check out a Samsung Captivate sometime. DANG, I don't know how they make it that bad. Even WITH assistance data, time to first fix can be 5-10 minutes. And good luck holding onto that fix unless you're standing out in an open field. USELESS for city navigation, quickly looking at a map, etc.
Oh, and civilian GPS isn't anywhere close to 1 metre accuracy on it's own (military GPS runs on two frequencies allowing complex ionospheric correction math to be done in the receiver increasing accuracy). When you see 1m fix accuracy (which actually is 1m with 95% confidence - there's still a 5% chance you're off by more than 1m) on a GPS receiver, additional assistance beyond civillian GPS is being used.
WAAS (Wide-Area Augmentation System) is the most common such assistance. It is an FAA system using two geostationary satellite to broadcast ionospheric correction data from known ground stations. This system is most useful the closer you are to a ground reference station, but always increases accuracy both by providing this correction data, and also by being two additional satellites to use in calculating a fix. Generically, this is a SBAS (Satellite-Based Augmentation System), and Europe has their own and other countries are developing such systems.
An older system called DGPS (differential GPS) is provided by the US Coast Guard (in the US) and provides similar data from land beacons. Few receivers currently use this system, though it was common in the days of SA (Selective Availability - the deliberate error once added to the civillian use GPS signal). DGPS is more expensive to implement (and WAAS was not available), has lower availability, but was absolutely essential to useful position fixes in the days of SA.
Finally, some modern GPS receivers make use of GLONASS. GLONASS is a very similar system to GPS, developed by the Russian government. It was allowed to degrade after the collapse of the USSR, and finally completely re-launched last October. Except at high latitudes, it provides no real benefit over GPS, however, it provides MORE satellite, more data, and a more accurate fix when combined with GPS. The greatest improvement is in areas such as urban canyons where the video of the sky is restricted. Given the high accuracy GPS alone provides, along with GPS' proven track record of availability, and the accuracy possibly with WAAS, there would be little incentive for manufacturers to quickly add GLONASS support to their product lines. Seeing this, the Russian government has a duty on all GPS navigation devices - that is waived if they support GLONASS. Given that GLONASS further enhances position accuracy and availability, there's no real reason NOT to add it to all devices world wide (possibly battery life). Expect most GPS receivers to support GLONASS within a couple years. Many, such as the new Garmin eTrex models, and the Qualcomm chipset used in the iPhone 4S and many Android phones, already support GLONASS.
Seeing this, do you still want to say assisted GPS isn't "real"? The GPS performance on my iPhone 4S will generally be better than the GPS performance of my old Garmin eTrex Vista. Almost instant time-to-first-fix thanks to assistance data. GLONASS support to provide approximately double the available satellites for a fix in low-signal areas. The Garmin's advantage, of course, is WAAS. Which gives it higher accuracy out in the open since it's able to correct for atmospheric errors. Either one is a highly accurate, modern GNSS (generic name for GPS, GLONASS, and similar systems) solution. I just wish Apple allowed developers to access the details of the GNSS status (how many satellites it sees, is using for the fix, detailed fix accuracy, etc). How I wish I could have an app that just gave me the technical GNSS data. Dang app store...
Now, if you want to see a BAD GNSS implementation check out a Samsung Captivate sometime. DANG, I don't know how they make it that bad. Even WITH assistance data, time to first fix can be 5-10 minutes. And good luck holding onto that fix unless you're standing out in an open field. USELESS for city navigation, quickly looking at a map, etc.
How many Android tablets out there support the European version of LTE which has many different versions by the way. Did it ever occur to you that there might not have been a chipset that could be crammed into the iPad and Apple is maybe waiting for the next generation technology? Nope.. You would rather come here, complain and offer your opinion as fact. Get your clue at the door on the way out.