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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  • dagamer34 - Sunday, September 11, 2011 - link

    On pg 15, Galaxy S uses a SGX 540 GPU, not 530. Other than that, great review!
  • Synaesthesia - Sunday, September 11, 2011 - link

    Staggering review, you really are the most comprehensive and scientific reviewer around, bravo!

    Samsung have really impressed with this phone, in terms of how much effort they have invested in the hardware and software. One thing still stands out for me, the battery life. While good, it still doesn't hold a candle to the iPhone 4, as shown on the charts.
  • LostViking - Saturday, September 17, 2011 - link

    What do you mean?
    Its about 30% worse when web browsing (mostly because of the much larger screen I reckon), but better in the other tests.

    If you are one of those old timers who actually use the phone for talking the SGSII is about 30 better ;)
    When I am low on battery, and don't have access to a charger, that's usually what I would prioritize.
  • xdrol - Sunday, September 11, 2011 - link

    For me the mentioned Cat 5 limit looks reasonable - you don't get user-level 2.0 Mbps because of the overhead of the PDCP/RLC/MACd protocols (about 15% -> 2.0 Mbps is 1.7 Mbps for IP).
  • wilky76 - Sunday, September 11, 2011 - link

    Alot of people that have the Samsung Galaxy S2 are suffering from framerate problems when using either 720p or 1080p in low light including myself.

    What basically happens is when the camera tries to focus in lowlight the framerates drop to around 13fps, then jump back upto around 30fps again, basically making any HD video recording useless in low light because of the stuttering, the only fix that is known is to drop the exposure to -2 as this stop the stuttering, or use 480p when indoors or poor light.

    Some folks have returned their SGS2 because of this problem, only to receive another with the same problem.

    There has been a couple of camera firmware updates on Samung own app site, which to this date still hasn't sorted the problem out & in some cases people that weren't suffering from this problem, now have it after updating the camera firmware.

    Can any of you guys at Anandtech test your SGS2 in low light with either 720p or 1080p to see if the mobile you received for reviewing also suffer from this problem.

    But what is strange is that not everbody has the framerate problem, so it could be due to which sensor you get with your SGS2, and could proberly be sorted with a firmware update eventually.

    Anyways people with this problem and there is a few can be found in this post over at XDA

    http://forum.xda-developers.com/showthread.php?t=1...
  • DrSlump - Monday, September 12, 2011 - link

    Hi, i have exactly the same problem with my samsung galaxy s2.
    I got casual stuttering (a frame loss) during normal light conditions and severe stuttering under low light conditions.
    As soon as the firmware raises the sensor gain to match the detected light, the framerate goes down to 25fps and when autofocus occours the framerate goes down to 13fps, and then returns back to 25fps when the autofocus is finished.
    I olso noticed that when i try to frame a tv or a monitor, severe banding occours. Even taking a video when the light source is a tv or a monitor, banding occours. Seems like the isp isn't able to compensate the frequency of the light source.
    In a lot of situations it's impossible to take a video due to the severe stuttering :(
    Any one of you has these problems? How to solve it?

    I would like to ask to the autor:
    did you notice some problem with the display? There is a thread in the xda-developers forum that speaks about the yellow tinting or faded out left side of the screen. Please can you report about this problem?
  • B3an - Sunday, September 11, 2011 - link

    Why dont you just admit it's the best phone around hands down? :) Not just the best Android phone. It's clearly miles superior to the outdated iPhone 4.

    Shame you yanks have had to wait forever to get it, only to get 3 different versions that dont even look as good and have ridiculous names. I've been using a GSII since April and it's just unmatched.
  • ph00ny - Sunday, September 11, 2011 - link

    This yank got it on the UK launch day and i've been enjoying it since
  • steven75 - Sunday, September 11, 2011 - link

    It's not better in battery life, audio quality, display resolution and sharpness, or the many ways that iOS is better (AirPlay, app selection AND quality), immediate OS updates, etc).

    Gread Android phone though for those interested in 4.3" displays, which definitely isn't everyone. Personally, I'd wait for the Prime.
  • steven75 - Sunday, September 11, 2011 - link

    Oh and outdoor display brightness, which even at 100% isn't a match for iPhone, but then it's even capped at 75% for temp reasons.

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