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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KPOM - Wednesday, October 17, 2012 - link
However, Apple made a point about anodizing in its display. Also, Apple has historically placed a premium value on industrial design so it is interesting to read more specifics. What has struck me about Apple is how much time they devote to things people don't notice consciously or will never see on a spec sheet, but which can unconsciously affect the user experience. The aluminum has a nice feel to it, and I can see why Apple would forgo putting a resin coating on it, even though it would make it less susceptible to scratching. Understanding the physics helps make clear what kind of compromises Apple needs to make.phillyry - Sunday, October 21, 2012 - link
As per emotional input:I actually look for this in the review and podcasts because it colours the facts.
While I find the facts to be interesting and a good way to pass the time, at the end of the day my purchase decision, like those of human beings in general, will be largely guided by the sentiment of the matter.
People want to know how happy others are with their devices. Just facts alone lack humanity. I personally love hearing opinions, side comments and anecdotes that give me insight into the thoughts, feelings and experiences of people who's opinions I hold in high regard, such as anand and the gang.
There's something to be said for the qualitative experience that comes with the daily use of the device as your primary 'phone'.
Many others may also be looking to hear the comradery, jest, and fun-casual tone that you can get on this site when these guys just let their opinions out or go off on technical tangents. If you listen to the podcasts it'll all make more sense.
phillyry - Sunday, October 21, 2012 - link
P.S. the feeling that someone else, like anand, has about the device is also important because, if you are considering buying one of these things than you're going to have it for a couple of years and won't want to feel stuck with it.Spunjji - Friday, October 19, 2012 - link
I have to agree here... I already know how anodizing works (not specialist knowledge, we were taught in high-school...) and even if I didn't, I'm not sure a 'phone review is the best place to learn. An outside link would have sufficed. The whole thing does basically say that Apple had no choice in the matter unless they change the design, and that's really the point there. They should have changed the bloody design.arghhh - Tuesday, October 16, 2012 - link
How is it as a phone? Iphone never has been good at its primary function (I take an old clamshell over most smartphones in that regard).Arbee - Tuesday, October 16, 2012 - link
Brian Klug covered voice quality in this writeup, and AT's previous iOS 6 review covered the new voice call features. The upshot is it's at least as good as any other smartphone, even if no cellphone can replace a hardwired slab of mid-60s AT&T bakelite :)manik. - Tuesday, October 16, 2012 - link
Awesome read.Tangey - Tuesday, October 16, 2012 - link
The gpu comparison table shows the new iPad running @200mhz, it actually runs @250mhz ( as did the gpu in the ipad2). In a previous article you used this incorrect 200mhz as a reference point to determine that the iphone5 was running its gpu @266mhz.My calculations based on the iphone5's performance relative to the ipad3 @ 250mhz, indicate to me that the 543mp3 in the iphone5 is running in excess of 300mhz, most likely 325mhz, which also happens to be an exact divider of the 1.3ghz clock of the CPUs.
DustoMan - Tuesday, October 16, 2012 - link
Have you ever looked into why phones from certain manufactures are so picky about their chargers? I've had phones from HTC, Motorola, and Samsung and I've had three wildly different experiences when it comes to what chargers will work in what devices. When I had an HTC Incredible, I could stick pretty much anything I wanted to it and it would charge. If the charger didn't have much current, it would charge slower than a charger with my current. My Galaxy Nexus would work with a few of my chargers, but the oddest thing would happen when I would try connecting it to a Griffin car adapter that had the 1.5A plug necessary to charge a first gen iPad. The only plug that would charge it consistently was a car adapter that I purchased that was branded Samsung. Even an adapter that Verizon sold me as being compatible wouldn't work. Finally the worst offender is my wife's Droid 2 Global. It will only charge with a Motorola adapter. Adapters that work with my Galaxy Nexus, which you would think would need chargers with a higher current, wouldn't work. To charge her phone on my PowerMat, I have to plug the phone into a reserve battery and then use the Powermat to charge that reserve battery while it's charging her phone. Stupid huh?zephxiii - Tuesday, October 16, 2012 - link
Yes i recall Motorola's earlier microUSB equipped phones to be very picky....especially if the battery went completely flat as it seemed like only Motorola chargers (or compatible) would breathe life back into them.