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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youwonder - Wednesday, October 17, 2012 - link
I find it kind of ...odd that the S3 has a much larger battery than the one X and the same SoC yet posts significantly worse LTE browsing numbers, and is the only phone using LTE to get worse results with it than using 3G(granted that is the international vers, doesn't look like they had time to do testing on the AT&T or verizon variant running 3G). Does the samoled screen really draw THAT much more power than an LCD? also there's this which makes me wonder more:http://blogs.which.co.uk/technology/smartphones/be...
Of course, I don't respect these guys as much as anandtech when it comes to accurate results, and they did things much differently (broadcasting their own 3g signal and putting all phones on max brightness), but still the odd results here make me wonder if a small mistake wasn't made.
Zink - Wednesday, October 17, 2012 - link
Max brightness gives the gs3 an advantage because its screen is so dim. The other phones are using LED lighting as well but they go much brighter and have to shine through the LCD panel.youwonder - Wednesday, October 17, 2012 - link
Good point, I guess it's mostly just me wondering why the GS3 LTE variant posts such horrible numbers even compared to it's 3G version when anand specs a good amount of time explaining why the opposite is true.phillyry - Sunday, October 21, 2012 - link
Don't know why but it does tank on LTE.rarson - Wednesday, October 17, 2012 - link
I'm getting so sick and tired of seeing the word "literally" injected into all sorts of sentences that it doesn't belong in. This word only needs to be used when describing something literal. It's not a synonym for "really" (not yet, anyway).andykins - Wednesday, October 17, 2012 - link
Alright, language purist. :Pjoos2000 - Thursday, October 18, 2012 - link
http://theoatmeal.com/comics/literallyphillyry - Sunday, October 21, 2012 - link
Great link. That's too funny - literally!dfonseca - Wednesday, October 17, 2012 - link
On the last page, section "Final Words" / "iPhone 5 Device Conclusions", it's written:> At a high level, the iPhone 5’s cameras appeared to be some of the least unchanged elements of the new device however in practice the improvements are significant.
"Least unchanged" means "most changed." It should probably say "most unchanged," or "least changed."
Nice review, kudos to all authors.
mattlach - Wednesday, October 17, 2012 - link
I had the original iPhone, followed by the iPhone 3G and then the iPhone 4, and just switched to a Samsung Galaxy S3 in July.When the original iPhone came out, while it was the first to do what it did - and that's why I bought it at its steep no-contract introductory price - it wasn't exactly revolutionary, everything in the market was moving in this direction, but it was pretty well executed and nothing else did it at the time.
I upgraded to the 3G on launch, as I thought the edge speeds were dreadful, but was disappointed, as the phone wasn't fast enough to take advantage of 3G, and AT&T's 3G was pretty mediocre anyway. It didn't get important features its competitors had, like copy and paste until very late in the game, and I started to think that I should have gotten an Android phone instead.
By the time I got the iPhone 4, I was tired of my slow 3G experience and just wanted an upgrade to something faster. The iPhone 4 was a good upgrade, but I really only got it because I didn't like AT&T's Android offerings at the time. I had been thinking about going to Verizon and getting an Android for some time. The 3G should have been my last iPhone, it was a mistake to buy the 4.
Having realized my mistake, I waited 2 long years with the 4 until I could finally get out of my AT&T contract and go to Verizon and get a GS3, and it felt great.
The additional freedom of what I run on my phone, not being controlled by Apple and their agenda as to what makes it into the App store, and the fact that I finally no longer had to have iTunes installed on my computer were fantastic.
My computer has been iTunes free for 3 months now, and it feels great!
I was concerned for a while that once the iPhone 5 was released, they would come out with something that would make me regret my choice of the GS3, but it turns out they didn't.
I'll likely never buy anything Apple again. It feels like a huge relief to say that.