iPad 3G Disassembly, 3G Video Streaming and GPS Improvements

[MacRumors]

The iPad 3G was delivered to customers on Friday, about a month after the launch of the Wi-Fi iPad. The main differences between the units are the inclusion of a 3G data module as well as GPS functionality in the newer model. iFixit has already performed a teardown of the new unit, though few surprises were found.

Some additional notes of interest:

- Gizmodo notes that Netflix works over 3G but with down sampled video. ABC's app, however, refuses to play over 3G and is Wi-Fi only.
- Dan Frommer suggests ABC's 3G limitation is due to content licensing issues rather than a technical limitation imposed by either Apple or AT&T. When questioned, AT&T deferred to Apple for specifics.
- Gizmodo also describes a comparison of GPS functionality between the iPad and the Phone 3GS. According to their tests, the iPhone 3GS locked onto the GPS signal faster, but the iPad was more accurate and consistent.
- A few MacRumors forum members noted similar improvements in GPS, finding the Navigon app to work much better on the iPad:

With the iPhone navigon would jump me around and tell me to get on the freeway when I was already on the freeway. With the iPad 3G ... It updated my position in real time while I was pulling out of my driveway ... 40 ft.

- TUAW notes that Skype over 3G connections failed (as expected. They report that 3rd party SIM cards worked properly in the iPad.

Article Link: iPad 3G Disassembly, 3G Video Streaming and GPS Improvements

 

[sasj15]

that was so fast

I don't like it when people purchase new stuff to disassemble

 

[rcandre2]

Why is that iPhone so big?

 

[leomac08]

I have had my iPad 3G for 5 hours..... and the GPS is fantastic!

Tried it while my sister was driving

and it moves

Apple gets an A+ with the GPS

 

[ethana]

PLEASE PLEASE PLEASE bring this new GPS chip to the new iPhone being announced at WWDC!

 

[muskratboy]

suggests ABC's 3G limitation is due to content licensing issues rather than a technical limitation imposed by either Apple or AT&T.

criminey, will we EVER get past all this nonsense licensing ********? wifi is ok, but 3G isn't?

one day, we'll look back on all this as a ridiculous fantasy-land of ignorance. i hope.

 

[zv470]

GPS? I thought iPad only had "assisted GPS" ie: WiFi and Cell-tower triangulation?

 

[ravenvii]

GPS? I thought iPad only had "assisted GPS" ie: WiFi and Cell-tower triangulation?

Assisted GPS doesn't mean what I think you think it means.

 

[om1]

GPS? I thought iPad only had "assisted GPS" ie: WiFi and Cell-tower triangulation?

The 3G version has real GPS. Also, assisted GPS does not mean triangulation only, it means that on GPS startup triangulation data from wifi and cell towers is used to bootstrap the GPS receiver with an estimated position. The GPS then takes over without the potentially long startup times that non-assisted GPS has.

 

[princealfie]

I want one so badly but right now I'm pawning off a bunch of stuff just to get one soon!

 

[nagromme]

I have had my iPad 3G for 5 hours..... and the GPS is fantastic!

Tried it while my sister was driving

and it moves

Apple gets an A+ with the GPS

Cool! Makes me look forward to the “iPhone (Glass Backplate)” or whatever catchy name the 4th-gen will have

GPS? I thought iPad only had "assisted GPS" ie: WiFi and Cell-tower triangulation?

That’s not assisted GPS. You’re talking about what the original iPhone had. Assisted GPS means you DO have a real connection to GPS satellites, but you’re ALSO getting assistance from cell towers. (Not just triangulation: actual signal-processing assistance from computers connected to the towers.) That means A-GPS can be faster and more accurate than an unassisted GPS unit.

Also, I notice that my iPhone 3G does keep tracking even when I drive out of cell coverage. The blue dot moves off the already-loaded image and across the gray grid of the Maps app (no visual data can arrive). But it does move. (However, if I START the Maps app with no coverage, IIRC, I get an error and it won’t even try to proceed. I could be mistaken. I’ve been wondering how 3rd-party GPS apps perform when out of cell range—the apps that have their map data built in. But I haven’t tried any yet.)

 

[zv470]

Thanks for the replies, it's clear now.

 

[distantrhythm]

The 3G version has real GPS. Also, assisted GPS does not mean triangulation only, it means that on GPS startup triangulation data from wifi and cell towers is used to bootstrap the GPS receiver with an estimated position. The GPS then takes over without the potentially long startup times that non-assisted GPS has.

I could be mistaken. I’ve been wondering how 3rd-party GPS apps perform when out of cell range—the apps that have their map data built in. But I haven’t tried any yet.)

So you need to have an active (micro) SIM card to use the GPS in the iPad 3G?

Meaning that the GPS costs at least $15 a month to use...

 

[jjahshik32]

Thats strange how the ABC app knows your using 3G and wont play it..

I have my Nexus one tethered to the iPad and I can play ABC app just fine.

 

[Davidkoh]

Thats strange how the ABC app knows your using 3G and wont play it..

I have my Nexus one tethered to the iPad and I can play ABC app just fine.

I was gonna say that this is just another reason not to buy the iPad 3G and get the wifi and tether .

 

[diddl14]

iPad 3G + MIFI

I'm using a NovoTel-2352 3G MIFI Router with my iPad, MacBook and iPhone.
Can only say that I so far found no limitations in video playback or with apps like Skype on the iPad/iPhone when using the MIFI's 3G (@7.2Mbps).

Location based services with the iPad+MIFI combination also works surprisingly good. At least in the city (Vienna) it found my position highly accurate. Not sure if the MIFI's AGPS plays a role here?

What I've noted is that the digital compass of the iPad also did its work. While walking, the map automatically rotated in walking direction, again highly accurate.

All in all I'm very happy with the combination of non-3G and MIFI although the build-in 3G clearly has advantages too

 

[foobarbaz]

PLEASE PLEASE PLEASE bring this new GPS chip to the new iPhone being announced at WWDC!

It seems unlikely that they would add a dedicated GPS chip to the iPhone. The prototype revealed that they already shrank the logic board significantly.

Plus the effect might be in the antenna.

 

[NorfolkMustard]

So you need to have an active (micro) SIM card to use the GPS in the iPad 3G?

Meaning that the GPS costs at least $15 a month to use...

Think about it a bit longer.... There you go.

 

[iEdd]

So you need to have an active (micro) SIM card to use the GPS in the iPad 3G?

Meaning that the GPS costs at least $15 a month to use...

Think about it a bit longer.... There you go.

lol. You need an active 3G sim to use the 3G in the 3G iPad too.

I don't know why it's so hard for everyone to understand that the iPhone has real GPS and what 'assisted' means, though.

Cell tower triangulation - ghetto GPS, roughly finds your position using 3 cell towers.

GPS - uses a GPS transceiver and satellites. More accurate.

Assisted GPS - uses a data connection to find the nearest satellites to reduce the connection time of GPS. From then, it's almost identical to GPS. If there's no data connection, it reverts back to regular GPS and finds the sats the usual way.

So an iPad or iPhone can track your position (latitude/longitude) without a sim card or data connection using GPS, but that's only any good to you for sat-nav you if you have saved map data.

It seems unlikely that they would add a dedicated GPS chip to the iPhone.

It already has one, right? (Source: iFixit)

 

[manu chao]

So you need to have an active (micro) SIM card to use the GPS in the iPad 3G?

Meaning that the GPS costs at least $15 a month to use...

From TUAW :

• Nate True: "GPS on the iPhone functions even with no SIM installed, so it should work on the iPad without subscription."

 

[alphaod]

I'm just disappointed the TomTom app does not work on the iPad; I was looking forward to that!

 

[Garsun]

GPS works without the $15 charge

So you need to have an active (micro) SIM card to use the GPS in the iPad 3G?

Meaning that the GPS costs at least $15 a month to use...

I waited for the g3 version because I wanted the GPS. It works great and I have not signed up for ATTs service. Now i'am glad I will not have to

 

[mcarling]

O2 has MicroSIM cards?

I realize that MiniSIM and MicroSIM cards have the same contact area. I can imagine that some MiniSIM cards could be cut down to the size of a MicroSIM card without damaging any of the electronics inside. Is that what was done to test the O2 card? Or do O2 offer MicroSIM cards?

 

[gnasher729]

So you need to have an active (micro) SIM card to use the GPS in the iPad 3G?

Meaning that the GPS costs at least $15 a month to use...

Not at all.

What happens when you turn on a GPS for the first time, it obviously doesn't know where it is, so it has to spend some time to find the satellites. That can take quite a while. With assisted GPS, the GPS asks the nearest cell tower where it is (roughly), and what time it is, and with that information it can calculate roughly where the satellites should be, and it doesn't have to search for them all over the sky, but it looks only in those places where the satellites actually are (that description is not technically accurate, but it explains it well enough). That's what is called "assisted GPS"; it can find the satellites much quicker when the device is turned on.

But obviously GPS will work just fine without the cell tower, it just takes maybe a minute or two to find the satellites initially. Once they are found, the GPS can easily hold on to them. And GPS is much much more precise then the information from cell towers, so the cell tower information will usually not be used.

Where assisted GPS helps again and where you lose out without 3G is in areas like cities with huge buildings where the GPS might lose sight of satellites. GPS needs four satellites in direct view, so if you are on a road with high buildings on each side, you might lose that. Assisted GPS then still knows where the cell towers are. The iPad can also spot nearby WiFi hotspots and with 3G available, it can lookup their positions in a database.

But as long as you are on the road without any huge obstacles, the iPad GPS will work just fine without 3G, exactly as good as for example any TomTom device.

 

[wizard]

WiFi and cell triangulation have nothing to do with assisted GPS!

GPS? I thought iPad only had "assisted GPS" ie: WiFi and Cell-tower triangulation?

Seriously read up on this.

Assisted GPS simply means that the computer gets info to derive position from a source other than the GPS sattilite. The GPS signals are still needed to derive postion but the computer doesn't need to listen to the GPS signal to get all the required data.

I'm trying to make the above simple as I can but you need to spilt the techniques used for cell or WiFi triangulation from those used with GPS positioning. By the way that doesn't mean that one technique can't be used to support another it is just that the term assisted GPS implies something different than you seem to understand.


Dave