The iPhone 5 Review
by Anand Lal Shimpi, Brian Klug & Vivek Gowri on October 16, 2012 11:33 AM EST- Posted in
- Smartphones
- Apple
- Mobile
- iPhone 5
GNSS: Subtle Improvements
Section by Brian Klug
Like the iPhone 4S and the iPhone 4 CDMA before it, Apple has gone with the GNSS (Global Navigation Satellite System) leveraging both GPS and Russian GLONASS which lives entirely on the Qualcomm baseband. In the case of the iPhone 4S and 4 CDMA, that was onboard MDM6610 and MDM6600 respectively, both of which implemented Qualcomm’s gpsOneGen 8 with GLONASS tier. Going to on-baseband GNSS is really the way of the future, and partially the reason why so many of the WLAN, BT, and FM combos don’t include any GNSS themselves (those partners know it as well). In this scheme GNSS simply uses a dedicated port on the transceiver for downconversion, additional filtering (on RTR8600), and then processing on the baseband. The advantage of doing it all here is that often it eliminates the need for another dedicated antenna for GNSS, and also all of the assist and seed information traditionally needed to speed up getting a GPS fix already exists basically for free on the baseband. We’re talking about both a basic location seed, precision clock data, in addition to ephemeris. In effect with all this already existing on the baseband, every GPS start is like a hot start.
There was a considerable bump in both tracking accuracy and time to an assisted GPS fix from the iPhone 4 which used a monolithic GPS receiver to the 4 CDMA and 4S MDM66x0 solution. I made a video last time showing just how dramatic that difference is even in filtered applications like Maps.app. GLONASS isn’t used all the time, but rather when GPS SNR is either low or the accuracy of the resulting fix is poor, or during initial lock.
With MDM9615 now being the baseband inside iPhone 5, not a whole lot changes when it comes to GNSS. MDM9615 implements gpsOneGen 8A instead of just 8, and I dug around to figure out what all has changed in this version. In version 8A Qualcomm has lowered power consumption and increased LTE coexistence with GPS and GLONASS, but otherwise functionality remains the same. MDM9x25 will bring about gpsOneGen 8B with GLONASS, but there aren’t any details about what changes in that particular bump.
I spent a lot of time playing with the iPhone 5 GNSS to make sure there aren’t any issues, and although iOS doesn’t expose direct NMEA data, things look to be implemented perfectly. Getting good location data is now even more important given Apple’s first party turn by turn maps solution. Thankfully fix times are fast, and getting a good fix even indoors with just a roof between you and clear sky is still totally possible.
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A5 - Tuesday, October 16, 2012 - link
Double the browsing time while moving to LTE and roughly the same in everything else despite double the performance is pretty impressive.rarson - Thursday, October 18, 2012 - link
I'm pretty sure they mentioned about a million times that "this is the new paradigm blah blah blah, where if you use heavy processing power more often, the battery life will diminish faster" (I'm paraphrasing here). I'm fine with that. The iPhone 5 shows some pretty impressive battery life in light workloads and doesn't actually do all that bad in heavy workloads despite how much number crunching it's doing, even though it might actually tank the battery life down to less-than-4S levels.It's a tradeoff: you get more power or longer battery life, depending on how you use it. The article paints this as a bad thing, but I disagree; it's obviously making much more efficient use of the hardware. Because of that, I definitely think the battery life overall is better, even though sometimes it might be worse. And you're still getting a lot more number crunching for the watts used.
Center - Tuesday, October 16, 2012 - link
In the intro, the screen specs on the iphone 5 is listed as 1136x960.. should be 1136x640.But great article as always, Anandtech!
Krysto - Tuesday, October 16, 2012 - link
I hope we'll see the same kind of thorough review of Samsung's Exynos 5 Dual chip, Anand.ltcommanderdata - Tuesday, October 16, 2012 - link
Isn't TI supposed to become the first shipping Cortex A15 SoC? I expect Anandtech to thoroughly review the first Cortex A15 SoC. There shouldn't be a need to go into the same detail (on the CPU side) for every subsequent one unless preliminary tests show something significantly different.Kidster3001 - Monday, October 22, 2012 - link
Samsung and Qualcomm do not ship generic ARM chips. They purchase licenses to use the ARM instruction set, not the chip design. Their chips are highly customized and perform differently.Using your logic to just review the first A15 class chip and consider the rest to be comparable is similar to just reviewing the first new car to be released every year and assume the rest will be comparable.
btw, TI is getting out of the business. I doubt they will ship first, or ever.
A5 - Tuesday, October 16, 2012 - link
Considering the fact that Krait got several articles here, I'd imagine that whatever the first shipping A15 chip is will get significant coverage.Wurzelsepp - Tuesday, October 16, 2012 - link
Great review, you really have to give Apple credit for building an amazing SoC.It's interesting to see how well the Adreno competes with SGX-543MP3, the new Nexus 4 with this GPU is going to be amazing.
Krysto - Tuesday, October 16, 2012 - link
One thing both the iPhone and the Intel Atom processors will keep lacking for a year from now, will be OpenGL ES 3.0 support. Apple might bring it to the new iPad 4 this spring, but the iPhone won't have it until the next iPhone, in the fall of 2013, obviously. Same with Intel, they won't be supporting it at least until end of 2013.In the meantime both Adreno 320 and Mali T604 are supporting it, and will come out this fall.
darwinosx - Tuesday, October 16, 2012 - link
A year from now and something 'coming out this fall". Right.