5G wont change everything, or at least probably not your things

 arstechnica.com  12/04/2019 13:00:16   Rob Pegoraro
Artist's impression of millimeter-wave 5G speeds.
Enlarge / Artist's impression of millimeter-wave 5G speeds.

The long-touted fifth generation of wireless communications is not magic. Were sorry if unending hype over the world-changing possibilities of 5G has led you to expect otherwise. But the next generation in mobile broadband will still have to obey the current generation of the laws of physics that govern how far a signal can travel when sent in particular wavelengths of the radio spectrum and how much data it can carry.

For some of us, the results will yield the billions of bits per second in throughput that figure in many 5G sales pitches, going back toearly specifications for this standard. For everybody else, 5G will more likely deliver a pleasant and appreciated upgrade rather than a bandwidth renaissance.

That doesnt mean 5G wont open up interesting possibilities in areas like home broadband and machine-to-machine connectivity. But in the form of wireless mobile device connectivity we know best, 5G marketing has been writing checks that actual 5G technology will have a lot of trouble cashing.

A feuding family of frequencies

The first thing to know about 5G is that its a family affairand a sometimes-dysfunctional one.

Wireless carriers can deploy 5G over any of three different ranges of wireless frequencies, and one of them doesnt work anything like todays 4G frequencies. Thats also the one behind the most wild-eyed 5G forecasts.

Millimeter-wave 5Goccupies bands much higher than any used for 4G LTE today24 gigahertz and up, far above the2.5 GHz frequency of Sprint, hitherto the highest-frequency band in use by the major US carriers.

At those frequencies, 5G can send data with fiber optic speeds and latency1.2 Gbps of bandwidth and latency from 9 to 12 milliseconds, to cite figures from an early test by AT&T. But it cant send them very far. That same 2018 demonstration involved a direct line of sight and only 900 feet of distance from the transmitter to the test site.

Those distance and line-of-sight hangups still persist, although the US carriers that have pioneered millimeter-wave 5G say theyre making progress in pushing them outward.

Once you get enough density of cell sites, this is a very strong value proposition, said Ashish Sharma, executive vice president for IoT and mobile solutions at the wireless-infrastructure firmInseego. He pointed in particular to recent advances in solving longstanding issues with multipath reception, when signals bounce off buildings.

There are a lot of "5G" stock images available. Some of them are more optimistic than others. This is one of the more optimistic ones.
Enlarge / There are a lot of "5G" stock images available. Some of them are more optimistic than others. This is one of the more optimistic ones.

Reception inside those buildings, however, remains problematic. So does intervening foliage. Thats why fixed-wireless Internet providers using millimeter-wave technology likeStarryhave opted for externally placed antennas at customer sites. Verizon is also selling home broadband via 5G in a handful of cities.

Below millimeter-wave, wireless carriers can also serve up 5G on mid- and low-band frequencies that arent as fast or responsive but reach much farther. So far, 5G deployments outside the US have largely stuck to those slower, lower-frequency bands, although the industry expects millimeter-wave adoption overseas to accelerate in the next few years.

5G is a little more spectrally efficient than 4G, but not dramatically so, mailed Phil Kendall, director of the service provider group atStrategy Analytics. He added that these limits will be most profound on existing LTE spectrum turned over to 5G use: You are not going to be able to suddenly give everyone 100Mbps by re-farming that spectrum to 5G.

And even the American carriers preaching millimeter-wave 5G today also say theyll rely on these lower bands to cover much of the States.

For example,T-MobileandVerizonstated early this year that millimeter-wave wont work outside of dense urban areas. And AT&T waited until it couldlaunch low-band 5G in late Novemberto start selling service to consumers at all; thelow-resolution mapsit posted then show that connectivity reaching into suburbs.

Sprint, meanwhile, elected to launchits 5G serviceon the same 2.5GHz frequencies as its LTE, with coverage that is far less diffuse than millimeter-wave 5G. Kendall suggested that this mid-band spectrum will offer a better compromise between speed and coverage: Not the 1Gbps millimeter-wave experience but certainly something sustainable well in excess of 100Mbps.

The Federal Communications Commission is working to make more mid-band spectrum available, but that wont be lighting up any US smartphones for some time.

(Disclosure: Ive done a lot of writing for Yahoo Finance, a news site Verizon owns.)

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Over the past year, 5G has gone from PowerPoint presentation to more-or-less shipping product, and that real-world experience has worn some holes through the persistent industry hype of presenting 5G as a “transformative” technology that will help doctors save lives and assist in steering self-driving cars. And its millimeter-wave variant has come off looking by far the worst.

None of the three carriers to launch with millimeter-wave 5G—AT&TT-Mobile, and Verizon—even published proper maps of that coverage at first. T-Mobile went furthest, offering a set of static images showing individual but mostly unlabeled streets in Atlanta, Cleveland, Dallas, Las Vegas, Los Angeles, and New York highlighted in its trademark magenta.

T-Mobile says it has significant 5G coverage in New York.
Enlarge / T-Mobile says it has significant 5G coverage in New York.

But Verizon only identified neighborhoods in its 5G launch cities. AT&T, meanwhile, used the fact-checking-immune phrase “select areas” to describe its millimeter-wave 5G reach in such places as Austin, New York, and San Francisco. Reviewers soon found this 5G service even more elusive than advertised, although it's also exceeded 2Gbps in such ideal circumstances as the network Qualcomm set up for a summit for press and analysts in Maui this week.

Only Sprint produced detailed 5G coverage maps before launching its service—but it has yet to tangle with millimeter-wave 5G at all. And even that coverage-friendly mid-band service blinked in and out of reach on different blocks in downtown Washington, DC, during my testing of Sprint’s HTC 5G Hub hotspot this fall.

AT&T's map shows heavy 5G coverage (in cyan) over New York as well.
Enlarge / AT&T's map shows heavy 5G coverage (in cyan) over New York as well.

Verizon finally posted more detailed 5G coverage maps in November, and they show a service with a reach that’s more like neighborhood Wi-Fi. In Washington, for example, the signal covers much of the vicinity of the White House and the Capitol but skips over most of Pennsylvania Avenue NW in between.

Limited walking around the District with a loaned Inseego MiFi M1000 hotspot—a $650 model Verizon introduced in July—suggested even patchier coverage than Verizon’s map advertises. Over five blocks south and west of the Capitol, the M1000’s screen showed a 5G signal once.

And that was in a very small spot at the intersection of 7th Street SW and Maryland Avenue SW; walking 15 feet east had the hotspot once again in 4G mode.

Sharma couldn’t answer why the M1000 had fared so poorly—that would probably require him walking with me during the test. But he did observe of 5G in general: “It works really well when you’re in the coverage area.”

Millimeter-wave may do best in crowded venues such as stadiums and convention centers, thanks to its ability to support more discrete devices than low- and mid-band 5G. But even there, early deployments aren’t covering entire arenas.

Outside of its optimal use cases, millimeter-wave’s fragility will probably leave it as the balsa wood of bandwidth solutions.

And just as 4G hasn’t banished 3G and 2G from the experience of users who go far enough into rural areas, 5G won’t make you forget about 4G. A November report from Ericsson predicted that worldwide, 5G would at best cover 65% of the world’s population by 2025.

It’s early days in 5G hardware, too

But can’t you just buy one phone that will speak all of these frequencies and wait for your carrier to catch up? No. The hardware itself suffers from the usual early adopter symptoms of limited compatibility and inefficient design yet still sells at a substantial premium over 4G phones.

Take the situation with the 5G service T-Mobile formally launched Monday on its existing low-band 600MHz spectrum, a move that allows a far more extensive coverage cartography than T-Mo’s old millimeter-wave maps (which have since vanished from its site).

But the two new phones T-Mobile announced to go with its “new” 5G, the $1,300 Samsung Galaxy Note 10+ 5G and the $900 OnePlus 7T Pro 5G McLaren, don’t support the carrier’s older millimeter-wave 5G. And the Galaxy S10 5G that works on its millimeter-wave can’t use this new service.

Qualcomm, the dominant US vendor of smartphone chipsets, jumped into the market with its first-gen X50 modem, which only supported millimeter-wave bands. Its X55 modem is fluent in more frequencies but still exists as a separate part in a phone outside of its core “system on a chip.”

Qualcomm's new QTM525 5G mmWave antenna module and Snapdragon X55 5G modem.
Enlarge / Qualcomm's new QTM525 5G mmWave antenna module and Snapdragon X55 5G modem.

That, in turn, keeps 5G phones larger, more expensive, and less battery-efficient than they would be with a 5G-included SoC. The situation isn’t as bad as it was with first-generation 4G phones—at least today’s 5G phones don’t require multiple charges per day—but they have been seen overheating in the field.

We should see phones that check off the necessary boxes—support for all 5G frequencies included in the core chipset—by early next year. Qualcomm announced its first fully-5G-compatible SoC, the Snapdragon 765, at that summit in Maui Tuesday, along with a higher-end Snapdragon 865 that will still require a separate 5G modem.

Motorola and Nokia promptly said they'd ship phones based on the 765; the latter's history of shipping affordable Android phones suggests the price of 5G may get a lot cheaper in 2020.

Next year is also when you can expect to see an iPhone ship with 5G onboard—a development possible thanks to Apple buying Intel’s 5G smartphone business this summer. So please hold all questions about 5G iPhones until then.

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Wireless carriers have largely avoided making 5G a mass-marketed product yet; for example, Wave7 Research analyst Jeff Moore commented in an email that Verizon “seems more or less indifferent to selling it.”

Note that AT&TSprint, and Verizon leave 5G out of their cheapest tier of unlimited plans—although their next-cheapest plans are often the only realistic choice for intensive users, thanks to their allocation of usable mobile-hotspot data caps. T-Mobile, meanwhile, announced Monday that it would include 5G on all of its postpaid and prepaid plans.

But the recent consumer launches by AT&T and T-Mobile, combined with the onset of more sub-$1,000 5G smartphones, will usher customers into a confusing situation. They’ll have a phone that may or may not work on the 5G near them, which may or may not be much like the 5G they’ve heard about in ads or on the news.

“By sticking with [millimeter-wave], Verizon has an easier marketing story—its 5G network is blazing fast—but risks consumer disappointment when customers realize that they rarely see the 5G network,” emailed Avi Greengart, president and lead analyst at Techsponential.

Verizon does plan to offer 5G over lower-band frequencies as well—which its consumer-group CEO Ronan Dunne told an investment conference in August would perform like "good 4G." But although it demonstrated 850 MHz 5G at Qualcomm’s summit, Verizon has yet to provide a timetable for the service expansion that Moore suggested would represent a catalyst for its so-far nascent consumer 5G business.

“The other carriers have a more challenging marketing task, and they will need to explain that there are tradeoffs between speed and coverage,” Greengart said.

Outside of its optimal use cases, millimeter-wave’s fragility will probably leave it as the balsa wood of bandwidth solutions.

He commended T-Mobile for emphasizing coverage more than speed in its own 5G rollout—make that its second 5G launch.

“At least with this launch T-Mobile isn’t promising a revolution, but it will bring faster wireless service to large parts of the country that may never get mmWave 5G from any carrier.”

AT&T may be worse off, since it began re-labeling its fastest 4G service as “5G E” in 2018. With its November low-band announcement, it now has three flavors on the menu: “5G E,” which isn’t 5G at all; “5G,” the low-band 5G that doesn’t have the speeds the industry’s touted; and “5G+” millimeter-wave service.

Branding that calls out millimeter-wave 5G as the high-performance variant can help avoid consumer disappointment but also invites people to think less of low-band 5G—perhaps as “5G minus,” “5G Light,” or “Basic Economy 5G.” This isn’t a great situation for app developers, either—and without apps that can show off 5G, consumers may wonder what the fuss was about.

“If you want your app to be hugely successful, it still needs to reach a lot of people,” said Amir Ghodrati, director of market insights at the analytics firm App Annie. “By requiring 5G, you would be limiting your consumer base pretty quickly.”

He suggested game developers might find it easier to take advantage of 5G on a gaming-subscription service like Apple Arcade: “Those are avenues in which you can really push the boundaries of hardware and speed.”

Ghodrati’s advice for the industry: dial back on the hype in favor of some honesty about 5G.

“It’s going to be very different in some cities versus others,” he said. “If you can tell them as much of that upfront as you can’t, you’re going to be in a much better position.”

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