Breakthrough Could Lead to Amplifiers for 6G Signals
With 5G just rolling out and destined to take years to mature, it might seem odd to worry about 6G. But some engineers say that this is the perfect time to worry about it. One group, based at the University of California, Santa Barbara, has been developing a device that could be critical to efficiently pushing 6G's terahertz-frequency signals out of the antennas of future smartphones and other connected devices. They reported key aspects of the device—including an "n-polar" gallium nitride high-electron mobility transistor—in two papers that recently appeared in IEEE Electron Device Letters.
Testing so far has focused on 94 gigahertz frequencies, which are at the edge of terahertz. "We have just broken through records of millimeter-wave operation by factors which are just stunning," says Umesh K. Mishra, an IEEE Fellow who heads the UCSB group that published the papers. "If you're in the device field, if you improve things by 20 percent people are happy. Here, we have improved things by 200 to 300 percent."
Journal References:
Wenjian Liu, Islam Sayed, Brian Romanczyk, et al. Ru/N-Polar GaN Schottky Diode With Less Than 2 μA/cm² Reverse Current - IEEE Journals & Magazine, (DOI: 10.1109/LED.2020.3014524)
Brian Romanczyk, Weiyi Li, Matthew Guidry, et al. N-polar GaN-on-Sapphire Deep Recess HEMTs with High W-Band Power Density - IEEE Journals & Magazine, (DOI: 10.1109/LED.2020.3022401)
Related: FCC Will Allow Wireless Devices to Operate in the 95 GHz to 3 THz Range
Atom-Thin Switches Could Route 5G, and Even 6G Radio Signals
Samsung's 6G White Paper: Available by 2030, 1,000 Gbps Peak Speed, 1 Gbps "User Experienced" Speed
Scientists Build Ultra-High-Speed Terahertz Wireless Chip
Related Stories
FCC clears path for terahertz wireless data
Never mind the possibilities opened up by millimeter wave 5G and other many-gigahertz technologies -- the FCC is already thinking about the next generation beyond that. The Commission has voted unanimously in favor of creating a category of experimental licenses that range from 95GHz to a whopping 3THz -- effectively, the limits of usable wireless technology. The Spectrum Horizons order would let companies experiment with this ultra-high frequency tech for as long as 10 years, and would make it easier for them to sell real-world products while they're in that test phase.
The measure also sets aside 21.2GHz of spectrum to share for unlicensed devices.
Atom-Thin Switches Could Route 5G and 6G Radio Signals
Two-dimensional, atom-thin materials are good for a lot of things, but until two years ago, nobody thought they'd make good memory devices. Then Deji Akinwande, Jack Lee, and their team at UT Austin tried it out. It turns out that sandwiching a 2D material like molybdenum disulfide between two electrodes makes a memristor—a two-terminal device that stores data as a change in resistance. In research reported last week, they've proved a very important potential application for these "atomristors"—analog RF switches for 5G and perhaps future 6G radios.
[...] The key figure of merit for RF switches is called cut-off frequency. It's a combination of on-state resistance and off-state capacitance, both of which should be low in a good switch. Terahertz values for cutoff frequency indicate that a device is a good candidate for an RF switch, and the experimental hBN[*] devices scored 129 terahertz. As part of the testing, the team transmitted real-time high-definition video at a rate of 8.5 gigabits per second using a 100 gigahertz carrier frequency, which they say is more than sufficient for 5G's streaming needs. At this data rate, several movies can be downloaded in a few seconds. They reported their results in Nature Electronics (DOI: 10.1038/s41928-020-0416-x) (DX).
[...] For 6G frequencies, which are expected to include frequencies in the terahertz range (300 to 3000 GHz), the UT Austin team is planning new laboratory measurements.
[*] hBN: hexagonal boron nitride and Wikipedia.
Samsung is planning for the commercialization of 6G wireless technology around 2028-2030, with a peak data rate of 1,000 Gbps (1 Tbps) and a user experienced data rate ("minimum achievable data rate for a user in real network environment") of 1 Gbps (this is set at 100 Mbps download, 50 Mbps upload in the case of 5G):
In the white paper, Samsung expects that the completion of the 6G standard and its earliest commercialization date could be as early as 2028, while mass commercialization may occur around 2030. Both humans and machines will be the main users of 6G, and 6G will be characterized by provision of advanced services such as truly immersive extended reality (XR), high-fidelity mobile hologram and digital replica.
Whereas 5G requirements mainly focused on performance aspects, Samsung defines three categories of requirements that have to be met to realize 6G services – performance, architectural and trustworthiness requirements. Examples of 6G performance requirements are a peak data rate of 1,000 Gbps (gigabits per second) and air latency less than 100 microseconds (μs), 50 times the peak data rate and one-tenth the latency of 5G.
[...] The white paper also introduces candidate technologies that could be essential to satisfy the requirements for 6G. These include the use of the terahertz (THz) frequency band, novel antenna technologies to enhance the coverage of high frequency band signals, advanced duplex technologies, the evolution of network topology, spectrum sharing to increase the efficiency of frequency utilization and the use of AI in wireless communications.
Samsung's 6G white paper (PDF) mentions 16K resolution VR, as well as "high-fidelity mobile holograms" and "digital replicas/twins" (basically detailed VR avatars) as possible applications:
Another challenge is sufficient wireless capacity. Note that current AR technology requires 55.3 megabits per second (Mbps) to support 8K display (with one million points), which can provide enough user experience on a mobile display. However, in order to provide truly immersive AR, the density should be largely improved and it will require 0.44 gigabits per second (Gbps) throughput (with 16 million points). In addition, XR media streaming may have similar demands to 16K UHD (Ultra High Definition) quality video. For example, 16K VR requires 0.9 Gbps throughput (with compression ratio of 1/400). The current user experienced data rate of 5G is not sufficient for seamless streaming. It is expected that the market sizes for VR and AR will reach $44.7 billion and $87 billion, respectively, by 2030.
[...] Users will be even able to go beyond observation, and actually interact with the digital twins, using VR devices or holographic displays. A digital twin could be a representation of a remotely controlled set of sensors and actuators. In this manner, a user's interaction with a digital twin can result in actions in the physical world. For example, a user could physically move within a remote site by controlling a robot in that space entirely via real-time interactions with a digital twin representation of that remote site.
Also at Wccftech.
Scientists build ultra-high-speed terahertz wireless chip:
To enable data transmission speeds that surpass the 5th Generation (5G) standards for telecommunications, scientists from Nanyang Technological University, Singapore (NTU Singapore) and Osaka University in Japan have built a new chip using a concept called photonic topological insulators.
Published recently in Nature Photonics, the researchers showed that their chip can transmit terahertz (THz) waves resulting in a data rate of 11 Gigabits per second (Gbit/s), which is capable of supporting real-time streaming of 4K high-definition video, and exceeds the hitherto theoretical limit of 10 Gbit/s for 5G wireless communications.
[...] fundamental challenges need to be tackled before THz waves could be used reliably in telecommunications. Two of the biggest issues are the material defects and transmission error rates found in conventional waveguides such as crystals or hollow cables.
These issues were overcome using Photonic Topological Insulators (PTI), which allows light waves to be conducted on the surface and edges of the insulators, akin to a train following railroads, rather than through the material.
[...] Their discovery could pave the way for more PTI THz interconnects—structures that connect various components in a circuit—to be integrated into wireless communication devices, to give the next generation '6G' communications an unprecedented terabytes-per-second speed (10 to 100 times faster than 5G) in future.
[...] "By employing THz technology, it can potentially boost intra-chip and inter-chip communication to support Artificial intelligence and cloud-based technologies, such as interconnected self-driving cars, which will need to transmit data quickly to other nearby cars and infrastructure to navigate better and also to avoid accidents."
[...] Areas of potential application for THz interconnect technology will include data centers, IOT devices, massive multicore CPUs (computing chips) and long-range communications, including telecommunications and wireless communication such as Wi-Fi.
Journal Reference:
Yihao Yang, Yuichiro Yamagami, Xiongbin Yu, et al. Terahertz topological photonics for on-chip communication, Nature Photonics (DOI: 10.1038/s41566-020-0618-9)
Previously:
(2020-07-15) Samsung's 6G White Paper: Available by 2030, 1,000 Gbps Peak Speed, 1 Gbps "User Experienced" Speed
(2020-06-02) Atom-Thin Switches Could Route 5G, and Even 6G Radio Signals
(2020-01-21) Record-Breaking Terahertz Laser Beam
(2019-03-17) FCC Will Allow Wireless Devices to Operate in the 95 GHz to 3 THz Range
(2018-03-30) Smaller and Faster: The Terahertz Computer Chip is Now Within Reach
(Score: 1, Insightful) by Anonymous Coward on Tuesday September 29 2020, @06:00AM (4 children)
If 5G brought COVID to us, 6G will get us Ebola and not Chy-nah but California will be to blame.
(Score: 1, Informative) by Anonymous Coward on Tuesday September 29 2020, @06:12AM
Protocol layer seven has almost arrived.
(Score: 1, Interesting) by Anonymous Coward on Tuesday September 29 2020, @11:33AM (2 children)
6G waves are so strong they will heat the air and cook everything until they catch fire and cause wildfires and global warming. 6G is also a rapist who will go around raping people and being all rapey, when it isn't busy infecting everyone with cancer. You'll long for the days when wimpy 5G would only give you COVID.
(Score: 0) by Anonymous Coward on Tuesday September 29 2020, @12:33PM
That's what I said.
(Score: 0) by Anonymous Coward on Tuesday September 29 2020, @03:26PM
But the 6G waves will kill the unwanted rape pregnancies, so at least we won't have all the unwanted rape babies.
(Score: 2) by Mojibake Tengu on Tuesday September 29 2020, @06:53AM (2 children)
Nice. I am looking forward for pocket version of
https://en.wikipedia.org/wiki/Active_Denial_System [wikipedia.org]
The edge of 太玄 cannot be defined, for it is beyond every aspect of design
(Score: 2) by DannyB on Tuesday September 29 2020, @01:29PM
Active Denial can get you into more trouble than saying No Comment.
(Is that an Active Denial system in your pocket, or something of equal or lesser value?)
The thing about landline phones is that they never get lost. No air tag necessary.
(Score: 0) by Anonymous Coward on Tuesday September 29 2020, @01:37PM
You will be boiled. Because you disrupt the communication and the network will see you as a threat.
To be eliminated by using phased array techniques, made possible by the 6G higher "tower density".
(Score: 2) by acid andy on Tuesday September 29 2020, @10:04AM
All the better to slurp you with.
Master of the science of the art of the science of art.
(Score: 4, Interesting) by Muad'Dave on Tuesday September 29 2020, @12:23PM (8 children)
1 THz is 1,000 GHz. How is 94 GHz even close?
(Score: 2) by DannyB on Tuesday September 29 2020, @01:31PM (1 child)
You beat me to it. I came here to point out that.
If I have 94 Gigabytes in my pocket, that must be close to Terabytes!
The thing about landline phones is that they never get lost. No air tag necessary.
(Score: 2) by takyon on Tuesday September 29 2020, @01:58PM
deciterascale
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 2) by c0lo on Tuesday September 29 2020, @01:57PM (5 children)
It's the wavelength. THz radiation (T-ray, T-light) [wikipedia.org] is defined by sub-mm wavelength range.
94GHz is about 3.2mm
Now, the thing is the emission power for portable devices in the THz range is small [wikipedia.org], in the miliwatt range. A transistor working at these frequency is necessary for amplification. While this may not be it (yet), it's pretty close - just need to triple the current frequency to reach the mm wavelength.
https://www.youtube.com/watch?v=aoFiw2jMy-0
(Score: 2) by RS3 on Tuesday September 29 2020, @03:42PM (1 child)
1) I've gotten pooped on here on this very board (SN) for being okay with "giga" being 1024^3 in computer context. "Oh, you're corrupting the SI system you bad awful person. Waaaa". But I guess since it's all based in powers of 10, it's okay for "terahertz" to be off by a factor of 10. [large grin!]
2) TWTs approach 100GHz (I suspect govt. has better ones), and klystrons go way way up. Wheels = portability. Or helium balloons. [yet another large grin!]
Seriously, has anyone worked on a solid-state TWT concept? Or did I just give away an invention (highly doubt I'm the first to think of that...)
(Score: 2) by Muad'Dave on Tuesday September 29 2020, @05:00PM
I don't know if you can find them online, but I have ancient copies of the Proceedings of the millimeter and sub-millimeter conferences from around 1965-ish. They talk about all sorts of cool things they came up with (probably on LSD) to generate and receive sub-mm RF. Carcinotron? Really?
I don't know if this is the same conference or not: https://spie.org/Publications/Proceedings/Volume/2250?SSO=1 [spie.org]
(Score: 2) by Muad'Dave on Tuesday September 29 2020, @04:56PM (1 child)
Being off by a factor of 3 is better than 10, I guess.
(Score: 2) by sjames on Wednesday September 30 2020, @12:53AM
Still out by a factor of 3 or so. I'll bet if I pay a $100 power bill with $30 dollars, they won't consider it to be on the threshold of paid in full.
(Score: 0) by Anonymous Coward on Tuesday September 29 2020, @07:07PM
"It's the wavelength. THz radiation (T-ray, T-light) [wikipedia.org] is defined by sub-mm wavelength range.
94GHz is about 3.2mm"
Uhm .... from your wikipedia link
"Wavelengths of radiation in the terahertz band correspondingly range from 1 mm to 0.1 mm."
So how is 3.2 mm less than 1mm?
(Score: 0) by Anonymous Coward on Wednesday September 30 2020, @03:09AM (1 child)
So if 5G is slower than 4G does this mean that 6G will be even slower than 5G? I can't wait!!!
(Score: 0) by Anonymous Coward on Wednesday September 30 2020, @12:03PM
Yeah but it's more betterer.