Cellular and 4G LTE

We’ve now talked about the cellular architecture of the HTC Thunderbolt and LG Revolution, it’s now the Droid Charge’s turn. The Thunderbolt has the privilege of being the sole 4G LTE smartphone capable of doing simultaneous voice and data on both 3G EVDO and 4G LTE. The LG Revolution and Droid Charge can both transact voice and data at the same time only when connected to 4G LTE. 

The Charge does this with a very interesting combination of two basebands. 4G LTE connectivity is accomplished with Samsung’s very own CMC220 baseband, which is a category 3 device (same as Qualcomm’s MDM9600, and LG’s L2000) - 50 Mbps / 100 Mbps for upstream and downstream respectively on 20 MHz channels.

Like all the other devices, the Charge uses Verizon’s 4G LTE network on its 700 MHz spectrum, in LTE Band 13. We’ve talked extensively about Verizon’s 4G LTE network architecture in an exploratory piece already, but for a quick refresher Verizon currently is using 10 MHz channels with FDD, and has a total of 22 MHz of bandwidth. Even in markets where Verizon has licenses for additional spectrum, currently only upper C is being used. This is my first time seeing Samsung’s CMC220 on Verizon. 

What’s particularly curious about the Charge is that there’s no Qualcomm baseband for CDMA2000. Both 1x and EVDO are handled by VIA Telecom’s CPB7.1 baseband. This is very interesting, as it’s the first time in a long while I’ve seen something other than Qualcomm used for a CDMA2000 baseband inside the United States, though in China Via Telecom is apparently a major player. For comparison, the Samsung Fascinate used Qualcomm’s QSC6085 baseband. This combination of things makes the Charge one interesting and unique device from a cellular perspective. 

We don’t have to disassemble anything either, as the FCC has some nice shots of the Charge’s main PCB showing both basebands sitting pretty next to Hummingbird and its PoP LPDDR2. Center bottom is the VIA Telecom 7.1 (you can even make out VIA), and above it is the Samsung CMC220. 

Before we get to performance, let’s also go over what the Charge exposes for controlling these two radios. Inside Wireless & Network and Mobile Networks is a system selection toggle. Tap this and you can change from “LTE automatic” to “CDMA mode.” The former lets the Charge hand up to LTE whenever it is available, the latter forces the Charge to only use EVDO and 1x data. If you’re in an LTE market and want to save some power, this is handy. However, there’s no ‘LTE only’ mode that would force the Charge to hang onto LTE a bit longer, although its behavior wouldn’t offer any power savings. 

 

I was very impressed with the way the Charge hands over from EVDO to LTE most of the time, and never found myself want for more low-level control. In this regard, Samsung has done a nice job keeping data sessions working across the two basebands. My only complaint is that every once in a while, the LTE data session sometimes stalls briefly – sometimes for a a few seconds, other times for a few minutes. When that happens, you’ll see the uplink green arrow blink, but no orange downlink arrow. Rebooting the device fixes things. 

I seem to have developed the bad habit of taking so long with devices that they see their first firmware update and fixes. Then issues that I’ve identified in the launch software are addressed, and I have to go re-test everything to find what new issues have appeared in their stead. The Charge received its first major update last week, which both fixed the broken WiFi hotspot functionality (which previously stopped working exactly when May ended), and also changed the Charge’s bars to closely mimic those of Android 2.3. 

The update purports to improve handover between 3G EVDO and 4G LTE, improve call time battery life, improve call quality, enhance browser performance, and also improve GPS fix times among other things. I honestly couldn’t detect a measurable improvement in handover (the stall issue I mentioned still persists), and as I’ll show later call time battery life is better by a very small margin. I’ll talk more about the other changes in their respective sections. 

One subtle difference I noticed is that I can’t update the PRL on the Droid Charge the same way I could on the Thunderbolt. Dialing *228 to do an over the air PRL download yields the following:

It appears that we now have confirmation that both LTE and CDMA are using the USIM/CSIM in the device for both their roaming capabilities and cellular identities. I asked Vivek to do the same on his LG Revolution evaluation unit and he saw the same behavior. Back with the Thunderbolt, the OTA download would appear to complete happily just like any other CDMA handset. Regardless, in theory, you should now be able to swap SIMs (and thus your number, account, and service) between at least three handsets on Verizon – wow, that’s one sentence I wouldn’t have ever believed I’d write a year ago. 

Display: SAMOLED - Pentile = SAMOLED+ Droid Charge LTE Performance Investigated
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  • GrizzledYoungMan - Wednesday, June 22, 2011 - link

    Howdy!

    I could use some wisdom from the thoughtful nerds at Anandtech here. I'm a Verizon subscriber (who won't be switching networks, on account of the fact that I like getting reception), and I've been holding onto my Blackberry Pearl for last three odd years.

    Seriously. Don't laugh. The reason being that I haven't been so impressed with any Android phone that has come out in recent memory. I really like having a hardware keyboard, and I've found that for the stuff I need to do most - messaging, calling, mapping - the Pearl was as good as the first and second generation Android phones, except not fat.

    Now, it's come time for me to move on. To what? The iPhone is out, since I'm not an asshole. And I would really prefer to get something with an LTE radio. So I'm left with the prospect of the Thunderbolt, which sucks juice like a fat baby, or the Droid Charge, which is just straight up ugly. And, in my experience, has a maddening color cast to the screen.

    In my mind, it's worth it to wait a few more months, after years of avoiding upgrades, for the Droid 3, Bionic, GS2, etc. Any thoughts on the following?

    I like the look of the Droid 3, and my hunch is that battery life would be at least reasonable without an LTE radio on-board. But would I miss that connectivity? Overall, I prefer faster connectivity to a dual core proc. The hardware keyboard on the Droid 3 would seem to be a big draw, but the keyboard on the Droid 2 is so awful that I feel like I'm taking crazy pills every time people rave about it.

    The Droid Bionic sounds like an awesome beast - and like something that could also replace my kindle, my ipod and my netbook to a limited degree - but I have an ugly hunch it's months and months away. And that when it does arrive, it's gonna be gigantic and require a portable nuclear reactor to run for more than a few hours.

    I hear that the Samsung GS2 is coming to Verizon, but is that likely to happen in my natural lifetime? And if it does, what are the odds that it also has an LTE radio without the accompanying diabetic-5-year-old appetite?

    Alright, this has degenerated into a semi-rant, but thoughts from others in the same situation are appreciated! Thanks!
    Reply
  • Pessimism - Wednesday, June 22, 2011 - link

    You're right that the QWERTY market for Android is sadly lacking. Motorola seems to be the only vendor even taking a decent crack at it. Downside is they refuse to open their handsets to the community (bootloader/system is locked down and encrypted up the wazoo) and they have already orphaned many of their earlier, otherwise capable droid phones on obsolete releases. Reply
  • GrizzledYoungMan - Wednesday, June 22, 2011 - link

    Yeah, the locked bootloader thing also bugs me. It really wouldn't if handsets shipped with stock Android, and some measure of confidence that the OS would be updated in a timely fashion. But given that handsets ship with absurd bloatware and crappy UI overlays - I guess that's what we need these dual core procs for, to get all that crap working? - and heinously slow update cycles, I want control of my own ROM.

    Sigh. I gotta say, this is all really frustrating. Relative to the choices I had back when RIM was king, the smartphone market seems to have gotten crappier. Reviewers get very excited about big screens and kickstands and video streaming (I mean, jebus, who gives a crap about video streaming? I need to live, people), without noticing that phones have gotten obese and slow and half-assed.
    Reply
  • PeteH - Wednesday, June 22, 2011 - link

    "The iPhone is out, since I'm not an asshole."

    C'mon dude, don't be that guy. Just say you don't want an iPhone.
    Reply
  • GrizzledYoungMan - Wednesday, June 22, 2011 - link

    Yeah, you're right. Maybe I am an asshole.

    I thought long and hard about the iphone. Unlike other Apple products which fall mind-blowingly short of the hype - I'm looking at you, OS X, you fat, slow, stupid bastard - It's clearly the best hardware package out there as far as size/performance/battery life, and iOS has definite advantages over Android (although neither is a clear winner in my mind, given the applications I have for a smartphone).

    But, I mean, man. I just can't do it. I can't be part of the whole Apple "thing" - the implied smugness, ignorance, the submission to an authority that clearly has contempt for me.

    Just can't do it.
    Reply
  • Omid.M - Wednesday, June 22, 2011 - link

    Yeah, seriously! I will admit when a product is well executed. I'm not the " I hate brand X" guy. I like BMW, I like the Hyundai Tiburon V6. The Nissan 370z...etc. If it's well-done, it's well-done.

    Apple makes a great product. It's just a different philosophy in terms of design and UX. They use high quality parts and their testing is good and pretty thorough. If there isn't a good Android phone out by the time there's an iPhone with a 4" screen and LTE on Verizon, I may go with iPhone. But, I do love the kind of apps that are available for Android, in terms of monitoring system resources, etc. Some cool stuff is available that you can't get on iOS unless you jailbreak.
    Reply
  • robco - Wednesday, June 22, 2011 - link

    "The iPhone is out, since I'm not an asshole."

    Actually with that comment, you proved that you in fact are...
    Reply
  • piroroadkill - Wednesday, June 22, 2011 - link

    You probably own an iPhone though, right? Reply
  • robco - Wednesday, June 22, 2011 - link

    I do, and I like it. But there are things about it I don't like. There are Android handsets that look good. I'm even open to WP7. I use a Mac, but it's a laptop. Say what you want, but Apple makes great notebooks. If I were in the market for a desktop, it would likely be a Windows box.

    I'm an asshole, but not because I own an iPhone. I was an asshole long before I got one. Assholes use all different kinds of technologies, drive different types of cars (not everyone who drives a BMW is a douchebag for example), live in all types of places. Being an asshole and owning an iPhone are mutually exclusive.
    Reply
  • name99 - Wednesday, June 22, 2011 - link

    "Being an asshole and owning an iPhone are mutually exclusive."

    You mean they are ORTHOGONAL.
    Reply

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