Cellular

So we’ve already mentioned that SGS2 contains Intel/Infineon’s latest and greatest X-Gold 626 baseband, which supports HSDPA 21.1 (Category 14) and HSUPA 11.5 (Category 7) support, though SGS2 actually only supports HSUPA 5.76 (Category 6) according to Samsung. Of course, this international edition includes quadband UMTS and GSM support.

I used the SGS2 on AT&T in the USA, and my particular market only has PCS 1900 MHz support, meaning both GSM and WCDMA carriers both only sit in the PCS 1900 MHz band. I remember that one of the first things I did with the SGS2 at MWC was check whether all of the same excellent dialer codes worked, and thankfully they do.

  

Samsung continues to have the absolute best field test / engineering menus of any handset vendor, and on the SGS2 dialing *#0011# gives you access to information about the current connected carrier, band, RCC state (what signaling state you’re in) and signal (ECIO and RSCP at the bottom). There’s a field marked HSPA+ used which I think has confused some people - this shows 1 when data is being transacted (DCH state). I should also mention that I’m incredibly grateful that SGS2 shows all the correct and proper status indicators for network connectivity at the top - 3G, H, and H+ appropriately, instead of this trend in the USA of calling every UMTS connectivity state “4G” - ugh. As an aside, it’s normal to see 3G when in the idle state, and then a negotiation up to H+ when in the DCH (Dedicated CHannel) state if you’re on an HSPA+ network. I haven’t seen H+ show when in the FACH (Forward Access Channel) state.

Samsung Galaxy S 2 - Network Support
GSM/EDGE Support 850 / 900 / 1800 / 1900 MHz
UMTS/HSDPA/HSUPA Support 850 / 900 / 1900 / 2100 MHz
HSDPA/HSUPA Speeds 21 Mbps / 5.76 Mbps
Baseband Hardware Infineon/Intel X-GOLD 626 HSPA+

I ran 318 speedtests on the SGS2 using the Ookla Speedtest.net application, and did our usual thing and come up with a histogram showing throughput for those tests. Again, this is more indicative of AT&T speed than what the SGS2 is capable of, given that I’ve seen other SGS2 users seeing much faster on other WCDMA networks - I’m insanely jealous of all of you. I tested throughout my 1900 MHz market in Tucson, Phoenix, and on the positively dreadful 850 / 1900 WCDMA network in Las Vegas, which remains completely unusable even when CES or any other conference isn’t happening. But I digress.

First up is downstream, which develops a nice little normal distribution when you run enough tests like we’ve done here.

Downstream Performance

Again this is really more indicative of what you’re going to see in the markets I’ve tested in with AT&T. Speeds top out at 7 or 8 Mbps if you’re very lucky, with performance most of the time between 2 to 4 Mbps. The average here is 3.11 Mbps, with a standard deviation of 1.56 Mbps. That sounds about right to me given how many of these things I run when I’m not even testing a phone.

I’m also aware of the whole AT&T HSDPPB (“4G” unlimited data) versus DPPB (3G unlimited data) SOC code thing and the corresponding difference in APN. I used them interchangeably for a week or so and honestly didn’t see any difference.

Upstream is next, where AT&T continues to employ lots of artificial shaping, limiting upstream to at maximum 1.7 Mbps.

Upstream Performance

 

I’ve heard speculation that AT&T is limiting the HSUPA category to 2 or 3 (which is 1.46 Mbps), or category 5 (2.00 Mbps), but neither of those line up nicely with the artificial-looking wall that seems to exist on AT&T at 1.7 Mbps. I’m very positive however that there’s shaping going on here, the last remaining question is whether it’s enforced by only allowing a certain HSUPA category, or shaping somewhere else in the network. It’d make sense to me at least to do the latter of those two. It’s disappointing because there’s definitely the potential for much speedier upstream than what I see here.

Last is latency, which looks pretty typical, though there are some outliers in the data entirely from the abysmal Las Vegas performance tests:

Latency

Average latency works out to be 147 ms, which is pretty par for UMTS as far as I’m concerned, unless you’re lucky enough to be somewhere with much better backhaul and a flatter IP-based network architecture.

For the most part, I’m very pleased with SGS2’s cellular connectivity situation, though there’s a bit more to talk about. I noticed that sometimes cellular connectivity will stop and become unresponsive for anywhere between a few seconds, and minutes at a time, requiring a battery pull or lots of patience before working again. Toggling airplane mode doesn’t work when that happens, and usually it’s manifested by the data-type indicator disappearing. I’m not sure what the story is here, but it seems like I’ve seen a lot of Samsung phones having data sessions randomly lock up and then come back after a while, lately.

In addition, Samsung makes the mistake of going with a signal bar visualization with very compressed dynamic range. Since the whole iPhone 4 debacle, I’ve seen something of a trend towards a strict linear scale (which makes more sense), but SGS2 definitely doesn’t go that route. It’s not a huge deal however, just something to be aware of. I’m willing to overlook that issue considering that getting the real story on connectivity is no harder than dialing *#0011# and looking at the real number.

I’ve also read a bunch of accounts which claim that the SGS2 has iPhone 4-like deathgrip, which needless to say piqued my interest. Of course, I’ve been religiously measuring unintended signal attenuation on every device I’ve encountered ever since, so the SGS2 doesn’t get spared that treatment.

Signal Attenuation Comparison in dB - Lower is Better
  Cupping Tightly Holding Naturally Holding in Case On an Open Palm
Samsung Galaxy S 2 18.4 5.9 - 12.2
Droid 3 16.0 11.3 - 5.0
HTC Sensation 15.0 10.0 8.0 0.0
Samsung Droid Charge 10.0 10.0 5.0 0.0
HTC Thunderbolt - LTE 5.3 2.5 - 4.4
HTC THunderbolt - EVDO 6.5 0.8 - 7.2
Verizon iPhone 4 16.5 15.5 9.0 7.9
LG Optimus 2X 13.7 9.3 - 5.9
Nexus S 13.3 6.1 - 4.3
Droid 2 11.5 5.1 - 4.5
BlackBerry Torch 15.9 7.1 - 3.7
Dell Streak 14.0 8.7 - 4.0
Droid X 15.0 5.1 - 4.5
AT&T iPhone 4 24.6 19.8 7.2 9.2
iPhone 3GS 14.3 1.9 3.2 0.2
HTC Nexus One 17.7 10.7 7.7 6.7

The data is actually quite interesting, with the SGS2 showing more than the 15 dB average attenuation in worst case, and an unusually high open-palm result as well. If you go back to the disassembly and look at that antenna module, you can start to see why this is so bad. It’s located right in the plastic bulge, and the active region of the antenna printed on the plastic is less than a mm separated from the exterior. The result is that though there’s obviously no galvanic contact (there’s a plastic insulating layer between), there still is some coupling and attenuation in the near field right here.

I honestly don’t think it’s an iPhone 4-level problem at ~18 dB in this worst case (which I’ll remind you literally involves both hands clasped around the device as close as possible), but it’s still more than average.

Inside the SGS2 2.4 and 5 GHz WiFi, GPS, and Audience
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  • shamalh108 - Monday, September 12, 2011 - link

    Thanks alot, going to do that today, however if you read my post above im not sure its an individual app causing it. Maybe i should root so i can wipe the battery stats and recalibrate, besides that im also going to purchase the offical extended battery from samsung, i dont mind losing slight slimness:)
  • ph00ny - Monday, September 12, 2011 - link

    I didn't even bother with rooting for a month or two until i wanted to try out chainfire plugins. Even in stock form, battery life was great. certainly better than my captivate.

    One thing to understand about SAMOLED screen is that it uses 0 power on black pixel and more power on white pixels. So maybe try out a darker themed wall paper and also check to see if you have widgets that have tendency to use up more juice than an alternative

    Also for an example, samsung's stock music app uses roughly half of Google's music app power consumption. It gets worse with spotify (offline mode of course)
  • Remeniz - Monday, September 12, 2011 - link

    The trick is to adjust the power saving features to suit and make sure very little is going on in the back ground. I only run GPS if I need too and the WiFi gets turned off when i'm out and about, unless I know i'm in a WiFi zone and want to browse the www.

    I get at least a days use out of my SGS2.
  • supercurio - Monday, September 12, 2011 - link

    Note:

    "When idle, processor goes back to 200 MHz"

    Idle - screen on or an using a wakelock to keep the device on its the case.
    Otherwise the whole CPU is turned literally OFF − everything frozen in RAM.

    And in this situation, the baseband, Wi-fi chip or an external timer will wake up the CPU and restore Linux kernel in a working state when needed, like if you received a new mail, or a phone call.

    I precise that because most people believe the CPU stays ON all the time but it's the opposite, with standard usage, the CPU is ON only a fraction of the day.
  • Lucian Armasu - Sunday, September 11, 2011 - link

    Brian, I don't think it's fair to compare the "tablet" version of A5 with the "smartphone" version of the Exynos and all the other chips. Even Nvidia's Tegra 2 has either 50% or 100% higher clock frequency for its GPU in the tablets, compared to the one in smartphones.

    It's very likely that all tablet chips are more powerful than the smartphones ones, and for all we know the iPhone 5 GPU will only one 1 GPU core instead of 2 like in the iPad 2, or they'll be clocked at a lower frequency.

    I know you'll review the iPhone 5, too, but I think you're setting a too low expectation for the Exynos and the others compared to the "A5 chip". You know what I mean? You should've at least thrown a Xoom or a Transformer in there to see how it fairs against the Tegra 2 phones.

    I hope at least you'll correct this in future reviews. Great review otherwise, though.
  • privater - Sunday, September 11, 2011 - link

    An iPad 2 can run sun spider 0.9 with 1980 score (4.3.5)
    If the Exynos is superior on every aspect of A5, the result is difficult for me to understand.
  • Lucian Armasu - Sunday, September 11, 2011 - link

    Just as I mentioned above, it's not fair to compare the tablet versions with the phone versions of the chips. All the latest smartphones get around 4000 in the Sun Spider test, but all tablets get around 2000 in that test, so even on the CPU side, it's still not a fair comparison.
  • Mike1111 - Sunday, September 11, 2011 - link

    Great review!

    But why are you so late with the review of the INTERNATIONAL version? I mean I would get it if you decided to wait for the US versions, but waiting almost 4 1/2 months and then publish a review of the international version only a week before the US versions get released? Seems strange to me...
  • ph00ny - Sunday, September 11, 2011 - link

    Brian said in the other reviews comment sections that he was waiting to get ahold of a review unit. I did offer mine if he was nearby but he's nearly on the west coast and i live in the opposite side of the country
  • shamalh108 - Sunday, September 11, 2011 - link

    Another pity is that even games from gameloft which are supposed to be adapted to the SGS2 cause significant heating of the phone.. for example the Asphalt 6 available for free in Samsung Apps .. it would be great if more games were coded to make better use of the SGS2 gpu ...

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