Don’t buy a 5G smartphone—at least, not for a while

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Enlarge / 5G is here, but that doesn't mean you have to buy into it.

2019 is going to be the year of 5G—at least, that's what the cellular industry keeps saying. We're going to see the launch of several 5G smartphones from OEMs like Samsung, Motorola, and OnePlus, and carriers will be tripping over themselves to tell you how awesome their new 5G networks are despite coming with a slew of asterisks. I would like to make something up about how ridiculous the 5G hype has gotten, but it's hard to top actual quotes from industry executives, like Verizon's claim that 5G will "dramatically improve our global society." Faster mobile Internet is coming, but should you care about it yet?

Qualcomm recently had its big 2019 chip announcement , and as the world's biggest provider of smartphone chips, that gives us a good idea of what the upcoming 5G hardware will look like. The industry is doing its best to hype 5G up as The Next Big Thing™, but 5G hardware in 2019 is going to be a decidedly first-generation affair. Early adopters for 5G will have to accept all manner of tradeoffs. And when there might not even be 5G reception in your area, it might be better to just wait the whole thing out for a year or two.

A 5G mmWave primer: Making use of the spectrum that nobody wanted

"5G" is a shorthand reference to the next generation of cellular network technology that is launching in 2019. The whole "G" naming scheme started in the 1990s with the launch of GSM, which was called the "second generation"—aka "2G"—of mobile networking technology. GSM upgraded early networks from analog to digital, and those old analog networks were retroactively given the name "1G." Since then, we've gotten new "G" numbers with major coordinated network upgrades about every 10 years. These iterations brought important features like SMS and MMS messages, IP-based networking and mobile Internet, and, of course, more speed.

Today, modern smartphones run on "4G" LTE, which operates somewhere in the 450MHz to 5.9GHz range. The move to 5G will include improvements to the existing LTE infrastructure, but the defining characteristic of 5G is the addition of a new chunk of spectrum in the 24GHz to 90GHz range. The industry has settled on calling this new 5G spectrum "mmWave" (millimeter wave), and it's going to require new hardware in your phone, new hardware on the towers, and big changes to current phone and network designs.

Enlarge / MmWave offers lots of spectrum, but it's difficult to use.

Qualcomm

We're used to these "G" network upgrades coming with a compelling sales pitch about how much better everything is going to be, but the move to 5G mmWave is not a slam-dunk argument. Since mmWave runs at a significantly higher frequency than LTE, that means it comes with no shortage of tradeoffs. MmWave has worse range and worse penetration compared to LTE. A mmWave signal can be blocked by buildings, trees, and even your hand. MmWave doesn't work well in the rain or fog, and the ~60GHz chunk of this spectrum can actually be absorbed by oxygen . That's right—a slice of mmWave spectrum can be blocked by  the air.

With so many issues to overcome, mmWave sounds like a terrible chunk of spectrum to build a mobile network in until you consider two key points: the higher-frequency means mmWave has plenty of bandwidth and low latency if you can get it, and most of all, the spectrum is available. MmWave isn't being used for much right now because it is such a pain in the butt to work with. So if you can figure out all the implementation problems, you suddenly have a vast amount of airspace to work with. That's actually the first thing these companies talk about when they bring up mmWave. It's all going to be really, really hard and complicated, they say, but it's going to be worth it.

LTE debuted in 2011, and these past seven years have seen significant progress in making 4G smartphone hardware smaller, faster, and more efficient. With 5G, we're going to lose plenty of this technical maturity initially by packing in tons of new and expensive 5G hardware.

Discrete 5G modems—More components, more power usage, smaller batteries

Smartphones today are almost entirely powered by a single chip, appropriately called an "SoC" or "System on a Chip." As the name suggests, these are the most basic parts you need to make a computer all on a single, tiny chip. There are usually lots of CPU cores, a GPU, an "ISP" for camera functionality, Wi-Fi, and more. RAM isn't technically included on this chip, but to save space, the RAM actually gets stacked  on top of the SoC. The main off-SoC component is the storage, and across the motherboard there will typically be a sprinkling of tiny chips for power management, audio, Bluetooth, NFC, and other things. From there, it's the motherboard's job to connect everything to everything else and then  get the hell out of the way so that as much as the phone as possible can be filled with battery.

The point is that space is at a premium inside a smartphone, and while you can't do much to control the size of core components like the SoC, camera, SIM card, or USB port, the battery is the one part that can be as large or as small as you want it to be. When you think "size" in a smartphone, you should think "battery." Anything that gets bigger means less battery. Anything that adds an extra component means less battery. The battery gets all the leftover space in a smartphone. (This is, basically,the headphone jack argument.)

These past few years, smartphone manufacturers have all been trying to convince us that we don't need a headphone jack, and the argument has been that removing them means less complexity and more space for battery. Razer CEO Min-Liang Tan even put a number to this argument : he said that skipping a headphone jack inthe Razer Phone meant the company could increase the battery capacity by 500mAh.

Why does this matter in an article about 5G? The short answer is that 5G mmWave is going to require a lot more hardware than 4G, which brings up all of these battery size and device-complexity concerns.

Enlarge / 5G requires a separate chip, even on Qualcomm's new SoC.

Qualcomm

Qualcomm's biggest advantage in the 4G era has been its modems. Through a combination of technology knowhow and intellectual property rights, Qualcomm is the only chip maker that can combine an SoC and modem into a single chip and sell it around the world at a low price.

Qualcomm's modem competition

Qualcomm is the only company with a single-chip SoC+modem solution that sees significant distribution around the world.

Samsung offersintegrated modems in its own Exynos SoC line, but in the US, China, Latin America, and Japan, Samsung devices still get Qualcomm chips. Huawei and MediaTek are in a similar situation: they can build onboard LTE, but the chips don't get world-wide distribution. Apple makes iPhone SoCs, but it uses a separate chip for the modem. Appletransitioned away from Qualcomm modems in the iPhone XS in favor of Intel modems, but that set offa litany of lawsuits between Apple and Qualcomm.

Qualcomm owns a lot of essential cellular patents in some territories, and it aggressively uses its IP to maintain modem dominance. The company has facedmany lawsuits frommany companies inmany countries for unfair patent licensing, but that hasn't stopped the market reality of everyone-but-Apple using Qualcomm modems.

This single-chip solution is a huge advantage, resulting in a smaller, less-complex, cheaper motherboard and more room for battery. Merging everything into a single chip also results in power savings while the phone is running, since, generally, one chip takes less power than two chips. For years, Qualcomm users have enjoyed SoCs with onboard 4G LTE modems, and the company rode this design advantage to market domination. Today, as a high-end SoC vendor, Qualcomm is basically a monopoly, with nearly every Android flagship using a Qualcomm SoC.

Qualcomm recently showed off its flagship SoC for 2019, the Snapdragon 855. While the company spent hours beyond measure hyping up the Snapdragon 855's 5G compatibility, it won't actually have a 5G mmWave modem onboard. The 855 will have LTE onboard, as usual, but 5G phones will need a separate modem—Qualcomm is going to lose its single-chip advantage for 5G. As explained above, this means less battery and more power usage.

We've already lived through the whole "first-gen network hardware" routine before. When the switch to 4G happened, the first batch of new 4G hardware arrived with the same discrete modem compromise that we'll see with 5G. The most famous example was the HTC Thunderbolt, the first 4G device on Verizon's network. This used Qualcomm’s Snapdragon MSM8655 SoC (before the simplified model numbers!) with a separate Qualcomm MDM9600 LTE modem. The Thunderbolt was a disaster, since it included all this new 4G hardware with only a 1400mAh battery. It was thick, hot, slow, buggy, and had terrible battery life. The Thunderbolt regularly makes lists of "the worst phones of all time," and one HTC employeeeven apologized for the phone's creation. New network hardware can be a disaster if you do it wrong.

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