Slashdot Mirror
TeraHertz Transmitter Can Push 100Gbps+ Wireless Speeds Via a Single Channel (ispreview.co.uk)
Mark.JUK writes:
A team of Japanese scientists working jointly for Hiroshima University and Panasonic have managed to develop a TeraHertz (THz) transmitter that is capable of transmitting digital data at a rate of 105 Gbps (gigabits per second) over a single channel using the frequency range from 290GHz to 315GHz. Previously it was only possible to achieve such speeds by harnessing multiple channels at the same time.
Professor Minoru Fujishima, Hiroshima University, said: "This year, we developed a transmitter with 10 times higher transmission power than the previous version's. This made the per-channel data rate above 100 Gbit/s at 300 GHz possible. We usually talk about wireless data rates in megabits per second or gigabits per second. But we are now approaching terabits per second using a plain simple single communication channel."
Professor Minoru Fujishima, Hiroshima University, said: "This year, we developed a transmitter with 10 times higher transmission power than the previous version's. This made the per-channel data rate above 100 Gbit/s at 300 GHz possible. We usually talk about wireless data rates in megabits per second or gigabits per second. But we are now approaching terabits per second using a plain simple single communication channel."
It also cooks a burrito in 2.7 seconds. :)
Anons need not reply. Questions end with a question mark.
The biggest caveat is distance and indeed many such lab tests have measured the distance of their THz transmissions in centimetres, which is somewhat limiting. A few teams are now starting to talk in terms of metres, but right now anything up to 10 metres can be a real stretch to achieve
As usual, distance is a huge consideration in such announcements. Not that I'm not interested; heck, 10m (~33ft) would be sufficient for most of the cases where I would personally care about high-speed wireless...if/when they can sustain such throughput at that distance.
TeraHertz Transmitter Can Push 100Gbps+ Wireless Speeds Via a Single Channel
Great! Does this mean that my "My Three Sons" torrent won't be stalled at 83% for days on end anymore?
When our name is on the back of your car, we're behind you all the way!
Yeah - now I can use my data up in less than 1/10 of a second.
If there is more capacity to begin with there is more speed available when you split it. Think about it you could provide a 10,000 people with 10Mbps service with just one 100Gbps access point!
The problem is this is in the higher frequency bands and according to wikipedia the EHF bands are only good for about half a mile.
Minimum threshold fixed. Thanks!
From TFA:
All of this sounds wonderful, but as usual there are some fairly sizeable catches to the promised performance improvement and as usual the press release doesn’t really touch on any of them. The biggest caveat is distance and indeed many such lab tests have measured the distance of their THz transmissions in centimetres, which is somewhat limiting.
A few teams are now starting to talk in terms of metres, but right now anything up to 10 metres can be a real stretch to achieve and even a big improvement over that still won’t cut it for Mobile communications. The idea of using THz for Satellite links is another highly contentious one because light cloud and rain could easily cause havoc.
Makes sense. The higher the frequency, the shorter the range due to attenuation (as another poster pointed out.) TFA talks about satellite links! Assuming they can get enough signal through water vapour, they'd probably need some hefty directional antennas.
This looks like a last-metre solution that could compete with Bluetooth. Anything longer than that is wishful thinking at this point.
If it weren't for deadlines, nothing would be late.
Without even reading the article, a quick back-of-the-envelop calculation says that ~300 GHz corresponds to ~1 mm. wavelength (for EM radiation in vacuum or near that in air).
That's in the far infrared range of the spectrum. Read: optical, line-of-sight surely. Well duh... optical signals can be modulated at high speed, we know that, used every day to pump data through glass fibers or change channels on your TV. Why is this news?
It only works at a range of a metre or two, and has zero penetration of walls and the like.
It could be useful for things like wireless, lossless video and fast local file transfers. You could put your laptop down on the desk, have it begin wireless charging and wirelessly connect to your monitor and external HDD. Or just plug one USB-C cable into it and enjoy operation free from interference and at much lower cost.
const int one = 65536; (Silvermoon, Texture.cs)
SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
It should be noted... that THz wireless is point-to-point. Like a laser. Even 100's GHZ are.
It also gets absorbed by objects and the atmosphere completely different. For the same reason that 5 GHZ doesn't go through walls well.
So this will not replace your current wifi's application.
This article takes advantage of a definition for "terahertz band" as indicated in the paper linked.
http://aip.scitation.org/doi/f...
The "terahertz" band is 300 GHz to 10,000 GHz, so anyone who does work at 300 GHz is working in the "terahertz" band. However, the SI terahertz unit is 1000 GHz, as another poster pointed out. So this is on the far far far low end of the terahertz band. It's like claiming you're flying when you run, because both your feet are off the ground at the same time...
The problem when a torrent is stalled for days is that nobody connected to the torrent has the necessary pieces and who knows if someone with the whole thing will connect to seed to everyone.
Even if it is only good for a few meters if it can be made cheaply enough I can see an application for in-rack connections, replacing 100GE cables and backplanes which are a bitch to build, source, maintain and install. I wouldn't mind seeing a standard for an in-rack wireless link which provided north-south and east-west connections via small straight cavities.
You could even have an in-chassis wireless standard that eliminates the intensive implementation of connectors and backplane. It would probably be more reliable without all those degradable parts in between.
The problem is the damn things can't penetrate paper!
Chewbacon
The Bible is like Wikipedia: written by a bunch of people and verifiable by questionable sources.
Yeah, 290-315 GHz is a channel bandwidth of 25 GHz 802.11ac at 5 GHz has a channel bandwidth of up to 80 MHz (e.g channel 155 is 5735-5815 MHz).
Basically what they're doing is equivalent to "harnessing multiple channels at the same time." They've just elected to call their use of 312.5 80MHz bands a single channel, while if 802.11ac uses more than one 80 MHz band they're saying it's using multiple channels. Kinda like saying your road can only transport so many cars per lane, while my road can transport more cars in its "single" lane (which is 300x wider than your lanes, I just haven't painted lane stripes on it).
802.11ac can (with a single antenna) manage 433 Mbps over an 80 MHz channel, or 5.4 bps / Hz of bandwidth. 105 Gbps over 25 GHz is then 4.2 bps / Hz of bandwidth. Since there's no improvement in bps per Hz of bandwidth, basically you could get these results simply by scaling up existing technologies to higher frequencies and greater bandwidth. (Higher signal-to-noise ratio allows channel data rate to exceed frequency.)
Sounds like an ideal doping model for the future. Single channel distribution margins will be AWESOME.
Don't hate the player, hate the middle men.
A 'singular oddity' is an event that cannot be explained and only happens when you are alone.
It's the band - radio operators have names for the bands, from 3m-30m, 30m-300m, etc... It's all around the number 3 for mathematical reasons relating wavelength to frequency. The band itself is often called the "terahertz" band, because it contains that frequency in the band. K0DEN
. Define sqrt(x) as something really evil like (x / rand()), and bury it deep. Watch your coworkers go nuts.
Programmers will quickly find a way to use, no, require, that bandwidth to be able to transfer four kilobytes of text embedded in a web page, and it will still take several seconds for the web page to render.
Mostly random stuff.
100% completely, it's infrared light and most materials will absorb them and become warmer
No, this is a tech forum, it's Greylisting Blocked Penis Spam
atmospheric absorbtion is not linear with frequency - or it'd be opaque to visible light.
There are a number of clear "windows" across the frequency spectrum.
Extrapolating anything from 2.45GHz in particular is unwise, as this was specifically left as an unlicensed ISM band in the first place because of its susceptability to path losses caused by water.