WiFi and baseband

In our iPad 2 preview I speculated that Apple might have moved entirely to Qualcomm for the iPad 2 baseband, and the most likely guess was to the same Qualcomm MDM6x00 used in the Verizon iPhone. Turns out that I was only partially right. Looking at the difference in weight between the Verizon and AT&T models on the Apple website should've been the dead giveaway, but I initially suspected the reason was more area dedicated to power amps for the GSM/UMTS version. 


Black RF window at the top, even on a white iPad.

The Verizon iPad 2 shares the same Qualcomm MDM6600 baseband as the Verizon iPhone 4. The AT&T (GSM/UMTS) iPad 2 on the other hand uses the same Infineon, ...errr Intel X-Gold 618 baseband as the GSM/UMTS iPhone 4. It's interesting to see Apple using two different basebands when one could have covered both CDMA2000/EVDO and GSM/UMTS, and faster HSPA at that rate. The X-Gold 618 just isn't super impressive anymore in a world dominated by HSDPA 14.4 and 21.1 compatible basebands. That said, it's a welcome improvement from the X-Gold 608 shared between the iPhone 3G, 3GS and GSM/UMTS iPad, which lacked HSUPA entirely, and thus had a maximum upstream rate of 384 kbps (UMTS speeds). 

GSM/UMTS (AT&T) iPad 2 - Network Support
GSM/EDGE Support 850 / 900 / 1800 / 1900 MHz
UMTS/HSDPA/HSUPA Support 850 / 900 / 1900 / 2100 MHz
HSDPA/HSUPA Speeds 7.2 Mbps / 5.76 Mbps
Baseband Hardware Infineon/Intel X-GOLD 618

CDMA (Verizon) iPad 2 - Network Support
CDMA2000-1xEV-DO 800 / 1900 MHz
Theoretical Downstream/Upstream 3.1 Mbps / 1.8 Mbps
Baseband Hardware Qualcomm MDM6600

The cellular enabled versions of the iPad 2 still are easily picked out by the black plastic strip at the top which is an RF window. Curiously, the color of the RF window is black even on the white iPad models, which seems a bit un-Apple. Maybe black made more sense since white plastic might eventually show some discoloration. Through testing the window seems to also be used for WiFi in addition to cellular. The GSM/UMTS version has a microSIM slot and comes with a SIM ejector tool in the package.

 

I found the microSIM incredibly difficult to eject on my AT&T iPad 2 compared to every other iDevice. You have to insert the ejector tool normal to the curved surface, which ends up being at an angle of nearly 45 degrees with respect to the back surface. It isn't how I expected things to work, and the tray itself is a bit awkward. 

I carried around the AT&T version of the iPad 2 and ran over 150 speedtests using Ookla's speedtest.net application. I averaged throughput of 2.76 Mbps down and 802 kbps up, with latency of 390 ms. Anand carried around the Verizon version and saw downstream speeds averaging 872 kbps down, 434 kbps up, and latency of 382 ms. 

3G Speed Comparison - Speedtest.net to best host
Provider / Data Verizon - (EVDO) AT&T - (UMTS/HSPA)
Max Downstream 1.679 Mbps 6.135 Mbps
Average Downstream 0.872 Mbps 2.759 Mbps
Max Upstream 0.837 Mbps 1.635 Mbps
Average Upstream 0.434 Mbps 0.802 Mbps
Average Latency 382 ms 390 ms
Minimum Latency 298 ms 239 ms

Pricing between the two providers is interesting. It appears that Verizon was careful to not compete with AT&T at the same data package points, instead targeting data packages other than the two 256 MB and 2 GB bundles AT&T already offers. At the same time, pricing at 3 GB on Verizon is exactly where you'd wind up should you run over 2 GB on AT&T and incur the automatic $10.00 overage charge. Interestingly enough, whereas AT&T bills you automatically when you run over your data caps, Verizon simply stops and lets you add more data before the billing cycle ends. It's an interesting distinction, certainly competition is good. In addition, there doesn't appear to be any activation charge for either AT&T or Verizon. 

3G Enabled USAiPad 2 Data Plan Pricing
Provider Verizon (CDMA2000/EVDO) AT&T (GSM/UMTS)
250 MB NA $14.99 / mo - $14.99 for each additional 250 MB
1 GB $20.00 / mo NA
2 GB NA $25.00 / mo -$10 for each additional GB
3 GB $35.00 / mo NA
5 GB $50.00 / mo NA
10 GB $80.00 / mo NA

So which of the two is the one to get in the US? Ultimately the decision about which is "better" is really a function of local coverage profile, speeds, and how much data you use (which will determine your pricing). If you're an iPad 1 AT&T user and used unlimited, you also have the option of grandfathering it in for some time as well. Unless you’re in an overloaded metropolitan area, AT&T 3G data speeds are undeniably faster. At the same time, Verizon has more EVDO coverage that, while slower, is generally more consistent. Verizon’s pricing also includes heavier data numbers than AT&T does, so if you’re looking for something to completely replace a notebook with and intend to not use WiFi, that’s a fairly big draw. 

Speaking of data use, I find the fact that the “Post PC” era includes implicit data caps (neither Verizon nor AT&T offer any unlimited data iPad packages to new customers) somewhat disturbing. I burned through just shy of 1 GB of my 2 GB AT&T plan in 3 days of use. By the time I got finished writing everything on my review sections, I had already used more than half.

 

Words cannot express my frustration - nay, rage - at the telecom industry's calculated assault on unlimited data plans, first in the mobile space, and now alarmingly with terrestrial DSL. Glass caps on both have always existed (200 or 250 GB for cable, 5 GB for essentially all mobile), but unless you clearly were abusing it, nothing happened. This move to tiered billing is a much more alarming trend. The above screenshot coupled with my use patterns (I have under 37 MB per day for the rest of the month? HA!) is precisely why I can't possibly see myself using the iPad 2 on a day to day basis. I hate watching a meter, but at least I do it. The problem isn't so much the number so much as the psychological effect of knowing you're eventually going to run into the celing. 

WiFi

The iPad 2 uses the exact same 802.11a/b/g/n WiFi + Bluetooth 2.1 EDR stack as its predecessor - the BCM4329. Like the iPad 1, the iPad 2 has 65 Mbps (long guard interval, 20 MHz channel, 1 spatial stream) 802.11n support on both 2.4 GHz and 5 GHz. Essentially WiFi speeds and behavior close to the AP is exactly the same as it was before. I’ve seen other WiFi stacks on mobile devices with “802.11n” support provide short guard interval 20 MHz rates of 72 Mbps, but nothing above, yet, so it’s fair to say that the iPad 2 WiFi authentication rate is about par with the competition. That said, Bluetooth 3.0 is already here on a bunch of other devices. 

WiFi Performance

Unfortunately, WiFi range on the iPad 2 is noticeably less than its predecessor, and throughput slows down much earlier on the iPad 2 than it does on the iPad 1. I tested with a WiFi - 3G (AT&T) model and found that I’m able to make it further away from the AP by a good 10 meters or so, but throughput even after you drop one WiFi bar on the iPad 1 is continually better than on the iPad 2. 

WiFi throughput also tells a similar story, it just isn’t quite as good as its predecessor. It’s a bit unfortunate since Apple certainly could’ve used this refresh opportunity to be the first to introduce a two spatial stream 802.11n device.

For now, the wrap up with regards to the iPad 2’s WiFi performance is that close to the AP, things are just like they used to be. At the edge of WiFi coverage, the iPad 1 edges out the iPad 2 at maintaining higher negotiated throughput and actual speeds. 

 

Apple's foray into iPad cases - Smart Covers Display Analysis
POST A COMMENT

189 Comments

View All Comments

  • VivekGowri - Saturday, March 19, 2011 - link

    I think it's $799, but I agree, it's too high. The equivalent iPad, at $729, is also way up there - really the only iPad that makes much sense as far as value goes is the base 16GB WiFi. I think the Xoom is probably going to have it's price cut by at least $100, if not $200, before it actually gets anywhere - ASUS took the right tack by putting it's lowest end Honeycomb tablet at $399. Reply
  • KoolAidMan1 - Saturday, March 19, 2011 - link

    Where the iPad really works for me is as a travel device and in the living room. The iPad is just much nicer to use with in-flight wifi. Small, no cable management, and the battery will outlast a LAX-JFK roundtrip. My laptop lives in the overhead storage bin.

    You mentioned that the iPad has replaced the ThinkPad in airports, and I think that is spot-on. It is just so much more convenient and manageable to use compared to a laptop. I've left the laptop at home twice and I didn't miss it much, aside from not being able to play Starcraft 2 when I'm on the road. :)

    The "sharing" aspect of the device has great advantages in a work environment, especially when you want to go over PDFs with a group of people. No need to crowd around or turn a laptop, just pass around the iPad.

    As for the living room and bedroom, self explanatory. Not being tethered to the home office in order to fire off email is nice. Ditto using it as a universal remote in the living room.

    It is a luxury device and a supplement, absolutely, but a damn good one.
    Reply
  • nickdoc - Sunday, March 20, 2011 - link

    Finally a sensible person. We are definitely on the same page. Reply
  • kevith - Sunday, March 20, 2011 - link

    "You're absolutely right" almost always really means: "I totally agree..." :-) Reply
  • relentlessfocus - Saturday, March 19, 2011 - link

    As always a real insight into the hardware. I'd like to make an observation about generalising from your own inability to find something that tablets add to your PC./smartphone mix to the larger sphere of buyers. Indeed most are not crazy and overly rich.

    My friends have a 2 year old child. I have no doubt that eventually she'll be reacting with laptops and desktops but my oh my how much my friends talk about the 3 of them with the iPad. Not an Anandtech thing... fine. A real life use. I think so.

    Jake Humphrys is the lead for BBC's Formula 1 coverage here in the UK. While talking live in the pits with his co-commentators he now holds an iPad cupped in his hand that he gracefully reads from and then puts to his side as he gets live update info from his directors as the show is broadcast. OK, its not an Anandtech thing but its a real life use for a tablet that you wouldn't do with a netbook or notebook.

    It's being used by coaching staff in sports and by doctors making their rounds in hospitals. It's used by major corporations for field workers running in house bespoke apps for catalogues and inventory and real time pricing etc. It's used by estate agents in the field with their clients and its used in trendy clothing shops like All Saints to display the entire store catalog for customers to browse. I could without a doubt put together 100 real life uses that "did figure out a use for it" distinctive from what you might do with a netbook or laptop or even desktop.

    Your reviews set the gold standard in so many ways but in this one way its a shame you brought such a limited perspective to the usefulness of touch tablets in the world at large. I understand that people who do certain kinds of work really do find that a touch tablet device may not be useful, indeed you may not own a pickup truck or headphone amplifier. But the slant of your article and some of the comments above implies a great generality than I think can be justified.
    Reply
  • Anand Lal Shimpi - Saturday, March 19, 2011 - link

    First of all, thank you for your kind words - I really do appreciate them.

    I don't doubt that there are specific uses for a tablet that a notebook cannot do as well. I mentioned one of these in the review - simply passing around the iPad for others to look at, information sharing, it's a lot easier to do this than with a clunky notebook.

    My point about the usefulness is that it's currently not powerful enough, flexible enough and ergonomic enough to completely replace a notebook. I'm not saying it won't get there, but I don't believe it's there today. The iPad 2 is a great device, but it's an augment to existing computing devices - and for some users that's tough to integrate into their existing workflow.

    If you can find a fit that makes sense however, it's a great device.

    Take care,
    Anand
    Reply
  • Azethoth - Sunday, March 20, 2011 - link

    Good article. However I do not think the point of tablets and smartphones are to replace netbooks. I think their point is to compete on apps. If they can do something critical to someone better than another form factor then they win a sale. I think it will turn out there are more apps that are tablet appropriate than netbook appropriate.

    Unless there are more interface revolutions I just do not think there can be a 100% intersection between netbook and tablet utility. So while netbooks will remain better at the things a lot of people complain about not being able to do on a tablet, tablets will eat their lunch market share wise because of the many more things they do good enough or perfectly.
    Reply
  • Fontanka - Sunday, March 20, 2011 - link

    "Workflow ", "Use", "Users","Usefulness".........

    That's not what most of the 15 million purchasers (and counting) are thinking about....they want to communicate, be entertained and diverted when NOT WORKING. The iPad delivers.

    Fontanka
    Reply
  • WaltFrench - Sunday, March 20, 2011 - link

    @Anand, let me second the kind words of @relentlessfocus.

    And also his point: a tablet and a notebook are largely incommensurable.

    Lightweight, sub $1000 notebooks with 11-hour battery life, compressed learning times and near-instant app startup don't exist.

    Likewise, notebooks don't have anywhere near the touchscreen's I/O capabilities, which you call out as great in iMovie and GarageBand. (I'd add the iOS app I use for writing Chinese as part of my studies, and the painting app used by high profile artists to create New Yorker covers.) Then, there's a new mix of software appropriate to mobile life, including the many “specialized” apps @relentlessfocus offered.

    I get that, by definition, our current workflows can't be optimized on a tablet. (Mine, with multiple screens on the desktop, and a bigscreen laptop, would be horrible. Why would I even think to try?) These things are "technical disruptors," "creative destructors," "inventor's dilemmas," however you want to characterize them. They enable new usage modes at the same time that they're not as good, or downright awful, for the old ones. They serve new customers better than the old; this is all old hat ever since Shiva got incorporated into the pantheon.

    But thanks for such a complete review, for those of us who happen to be dabbling in devices that enable new functions, new activities.
    Reply
  • Anand Lal Shimpi - Sunday, March 20, 2011 - link

    I believe we're actually in agreement here. The tablet is a disruptive form factor and a disruptive device. In the article I state that I believe there's a glorious future for tablets, however I believe we're still at an early point in the evolution. Since we're operating on a faster-than-moore'slaw-curve here, you're looking at a 12 month product cycle with these things. As such I believe a cautious approach to investment is better, especially given the price points we're talking about.

    By all means, if you have the money to spend and have a genuine use for it - the iPad 2 is a great device. I'm genuinely giving the iPad 2 another chance, I really wanted to use the iPad 1 I just found myself carrying it and a notebook wherever I went.

    For example, I'm traveling now for CTIA but I brought the MacBook Air. I'd much prefer reading comments on the iPad 2, but I like responding to them on the Air. I don't really know what the right solution is to that problem. It can't be to have one device for reading web pages and another device for contributing to web sites? I believe there's still a lot of work to be done here, that's all I'm saying - not that the iPad or the tablet are doomed.

    Take care,
    Anand
    Reply

Log in

Don't have an account? Sign up now