UPDATE 5 July 2023: All’s quiet on the cellular front. The self-imposed cellular industry deadline for 6G rollouts (2030) is creeping closer but still several years away. Currently, the industry has its hands full with 5G Advanced, the latest in a tradition of inevitable fine-tuning that comes after each cellular generation (think 3.5G and 4G LTE). In fact, the industry standards organization, 3GPP, likely won’t even begin coordinating work on 6G standards until 2027.
In the meantime, there’s already plenty of technical ammunition to stockpile for when it comes time for everyone to sit down at the table and hash out what 6G will finally, ultimately look like. Since this story was originally published, research continues into expanding cell signals into the terahertz range, which remains both the most obvious and flashiest option for pursuing every cellular generation’s mandate: faster speeds and lower latencies. As with millimeter waves in 5G, terahertz waves bring a host of research questions beyond just “can this part of the spectrum be used to send and receive signals?”
One key research area already emerging is figuring out how to create new metamaterial-based reconfigurable intelligent surfaces. Such surfaces would respond automatically to changes in the surrounding electromagnetic environment to better transmit notoriously short-distanced terahertz waves, particularly in busy and noisy locations like cities. The desire to speed up wireless signals beyond even 5G has also driven early research into new memristors and techniques to cool transistors so that the physical network components can keep up with their electromagnetic counterparts. Elsewhere, work continues on signal modulation and encryption for 6G’s potential new frequencies.
For now, the research is still basic enough, and exploratory enough, that there hasn’t been any cause for a kerfuffle. Expect that to change as we inch closer to 2027ish and standards start being hashed out for real. Just as in 5G, companies will have different priorities and different implementations, and there will still be a lot of money and prestige in getting their versions set in stone. Of course, the fervor will also depend on how much the industry decides to hype up 6G after 5G has so far struggled to live up to the promise. —IEEE Spectrum
Original article from 29 November 2021 follows:
When wireless researchers or telecom companies talk about future sixth-generation (6G) networks, they’re talking mostly about their best guesses and wish lists. There are as yet no widely agreed upon technical standards outlining 6G’s frequencies, signal modulations, and waveforms. And yet the economic and political forces that will define 6G are already in play.
And here’s the biggest wrinkle: Because there are no major U.S. manufacturers of cellular infrastructure equipment, the United States may not have the superpowers it thinks it does in shaping the future course of wireless communications.
While many U.S. tech giants will surely be involved in 6G standards development, none of those companies make the equipment that will comprise the network. Companies like Ericsson (Sweden), Nokia (Finland), Samsung (South Korea), and Huawei (China) build the radio units, baseband units, and other hardware and software that go into cell towers and the wired networks that connect them.
As one example, equipment manufacturers (such as China’s Huawei and ZTE) will probably push for standards that prioritize the distance a signal can travel, while minimizing the interference it experiences along the way. Meanwhile, device makers (like U.S. heavyweights Apple and Alphabet) will have more stake in standardizing signal modulations that drain their gadgets’ batteries the least.
How such squabbles might be resolved, of course, is still an open question. But now is arguably the best time to begin asking it.
6G is—and isn’t yet—around the corner. When the Global Communications Conference (Globecom) begins in Madrid this December, attending researchers and telecom executives will find it features no fewer than five workshops devoted to 6G development. Compare that to the 2020 iteration of the IEEE Communication Society’s annual conference, which—pandemic not withstanding—included nothing 6Grelated beyond a 4-hour summit on the topic. And if you step back one year further to Globecom 2019, you’ll find that 6Gwas limited to a single technical talk.
Cellular standards are developed and overseen by a global cellular industry consortium, the 3rd Generation Partnership Project (3GPP). Past wireless generations coalesced around universally agreed-upon standards relatively smoothly. But early research into 6G is emerging in a more tense geopolitical environment, and the quibbles that arose during 5G’s standardization could blossom into more serious disagreements this time around.
At the moment, says Mehdi Bennis, a professor of wireless communications at the University of Oulu, in Finland, home of the 6G Flagship research initiative, the next generation of wireless standards is quite open ended. “Nobody has a clear idea. We maybe have some pointers.”
To date, 6G has been discussed in terms of applications (including autonomous vehicles and holographic displays) and research interests—such as terahertz waves and spectrum sharing. So for the next few years, whenever a so-called “6G satellite” is launched, for example, take it with a grain of salt: It just means someone is testing technologies that may make their way into the 6G standards down the line.
But such tests, although easily overhyped and used to set precedents and score points, are still important. The reason each generation of wireless—2G, 3G, 4G, and now 5G—has been so successful is because each has been defined by standards that have been universally implemented. In other words, a network operator in the United States like AT&T can buy equipment from Swedish manufacturer Ericsson to build its cellular network, and everything will function with phones made in China because they’re drawing on the same set of agreed-upon standards. (Unfortunately however, you’ll still run into problems if you try to mix and match infrastructure equipment from different manufacturers.)
5G and its predecessors have been successful because they’ve been universally implemented. 6G still has time to congeal—or not.
In 2016, as the standards were being sorted out for 5G, a clash emerged in trying to decide what error-correcting technique would be used for wireless signals. Qualcomm, based in San Diego, and other companies pushed for low-density parity checks (LDPC), which had been first described decades earlier but had yet to materialize commercially. Huawei, backed by other Chinese companies, pushed for a new technique in which it had invested a significant amount of time and energy that it called polar codes. A deadlock at the 3GPP meeting that November resulted in a split standard: LDPC would be used for radio channels that send user data and polar codes for channels that coordinated those user-data channels.
That Huawei managed to take polar codes from a relatively unknown mathematical theory and almost single-handedly develop it into a key component of 5G led to some proclamations that the company (and by extension, China) was winning the battle for 5G development. The implicit losers were Europe and the United States. The incident made at least one thing abundantly clear: There is a lot of money, prestige, and influence in the offing for a company that gets the tech it’s been championing into the standards.
In May 2019, the U.S. Bureau of Industry and Security added Huawei to its Entity List—which places requirements on, or prohibits, importing and exporting items. Sources that IEEE Spectrumspoke to noted how the move increased tensions in the wireless industry, echoing concerns from 2019. “We are already seeing the balkanization of technology in many domains. If this trend continues, companies will have to create different products for different markets, leading to even further divergence,” Zvika Krieger, the head of technology policy at the World Economic Forum told MIT Technology Review at the time of the ban.The move curtailed the success Huawei originally saw from its 5G standards wins, with the rotating chairman, Eric Xu, recently saying that the company’s cellphone revenue will drop by US $30 billion to $40 billion this year from a reported $136.7 billion in 2020.
As fundamental research continues into what technologies and techniques will be implemented in 6G, it’s too early to say what the next generation’s version of polar codes will be, if any. But already, different priorities are emerging in the values that companies and governments in different parts of the world want to see enshrined in any standards to come.
“There are some unique, or at least stronger, views on things like personal liberty, data security, and privacy in Europe, and if we wish our new technologies to support those views, it needs to be baked into the technology,” said Colin Willcock, the chairman of the board for the Europe-based 6G Smart Networks and Services Industry Association, speaking at the Brooklyn 6G Summit in October. Bennis agrees: “In Europe, we’re very keen on privacy, that’s a big, big, I mean, big requirement.” Bennis notes that privacy is being built into 5G “a posteriori” as researchers tack it onto the established standards. The European Union has previously passed laws protecting personal data and privacy such as the General Data Protection Regulation (GDPR).
So how will concepts like privacy, security, or sustainability be embedded in 6G—if at all? For instance, one future version of 6G could include differential privacy, in which data-set patterns are shared without sharing individual data points. Or it could include federated learning, a machine learning technique that instead of being trained on a centralized data set uses one scattered across multiple locations—thereby effectively anonymizing information that malicious actors in a network might otherwise put to nefarious purposes. These techniques are already being implemented in 5G networks by researchers, but integrating them into 6G standards would give them more weight.
The Washington, D.C.–based Alliance for Telecommunications Industry Solutions launched the Next G Alliance in October 2020 to strengthen U.S. technological leadership in 6G over the course of the next decade. Mike Nawrocki, the alliance’s managing director, says the alliance is taking a “holistic” approach to 6G’s development. “We’re really trying to look at it from the perspective of what are some of the big societal drivers that we would envision for the end of the decade,” Nawrocki says, citing as one example the need to connect industries previously unconcerned with the wireless industry such as health care and agriculture.
If different regions—the United States, Europe, China, Japan, South Korea, and so on—find themselves at loggerheads about how to define certain standards or support incompatible policies about the implementations or applications of 6G networks, global standards could ultimately, in a worst-case scenario, disintegrate. Different countries could decide it’s easier to go it alone and develop their own 6G technologies without global cooperation. This would result in balkanized wireless technologies around the world. Smartphone users in China might find their phones unable to connect with any other wireless network outside their country’s borders. Or, for instance, AT&T might, in such a scenario, no longer buy equipment from Nokia because it’s incompatible with AT&T ‘s network operations.
Although that’s a dire outcome, the industry consensus is that it’s not likely yet—but certainly more plausible than for any other wireless generation.
This article appears in the December 2021 print issue as “Geopolitics Is Already Shaping 6G.”
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