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Terahertz Wireless Chip Will Bring 30Gbps Networks

samzenpus posted more than 2 years ago | from the we-can-build-it-faster dept.

Network 177

MrSeb writes "Rohm, a Japanese semiconductor company, has created a silicon chip and antenna that's currently capable of transmitting 1.5Gbps, with the potential to scale up to 30Gbps in the future. While this is a lot faster than anything currently on the market, the significant advance here is the reception and transmission of terahertz waves (300GHz to 3THz) using a chip and antenna that's just two centimeters long. Rohm says it will only cost $5 when it comes to market in a few years — a stark comparison to current terahertz gear that's both large and expensive. The problem with terahertz transmissions, though, is that it's highly directional — with a submillimeter wavelength, it's more like a laser than a signal. Terahertz waves might enable awesome device-to-device networks, but it isn't going to bring 30Gbps internet to a whole city block. More interestingly, submillimeter terahertz radiation is the next step up from the gigahertz radiation used in full-body millimeter wave scanners. Terahertz waves can not only see through clothing, but can also penetrate a few millimeters of skin."

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177 comments

Next mod... (2, Funny)

ThinkDifferently (853608) | more than 2 years ago | (#38191282)

Build your own fully body scanner.

Re:Next mod... (5, Funny)

ddd0004 (1984672) | more than 2 years ago | (#38191412)

This could be very handy for searching for government implanted transmitters inside your own body. I look forward to a day when we can cast aside our crudely fashioned aluminum hats

... Nothing that IBM hasn't allready done.... (0)

Anonymous Coward | more than 2 years ago | (#38191514)

In the early 90's IBM was building microprocessors capable of Tara-Hertz frequency for the Military.

Re:... Nothing that IBM hasn't allready done.... (0)

Anonymous Coward | more than 2 years ago | (#38192052)

Tara, you say?

Re:... Nothing that IBM hasn't allready done.... (0)

Anonymous Coward | more than 2 years ago | (#38192784)

ra boom dee ay say I!

Re:... Nothing that IBM hasn't allready done.... (0)

Anonymous Coward | more than 2 years ago | (#38193096)

No they weren't. First, it's "terahertz", second, no.

Re:Next mod... (1)

Joce640k (829181) | more than 2 years ago | (#38191816)

Which part of "can penetrate a few millimeters of skin" is 'interesting' rather than 'scary'?

Re:Next mod... (5, Informative)

Anonymous Coward | more than 2 years ago | (#38192008)

Terahertz radiation is non-ionizing, unlike say X-Rays. This type of radiation is used in things like bomb detectors and to inspect explosives and other unstable compounds because it can penetrate a few millimeters but does not break down molecular bonds.

Re:Next mod... (2)

sexconker (1179573) | more than 2 years ago | (#38192242)

Terahertz radiation is non-ionizing, unlike say X-Rays. This type of radiation is used in things like bomb detectors and to inspect explosives and other unstable compounds because it can penetrate a few millimeters but does not break down molecular bonds.

Non ionizing != safe.
There's a reason there's a little grill on your microwave door window.

Re:Next mod... (2, Informative)

Anonymous Coward | more than 2 years ago | (#38192340)

Non ionizing != safe.
There's a reason there's a little grill on your microwave door window.

Somehow I doubt these will be transmitting a 1000W. It can still be safe, even without the little grill.

Re:Next mod... (0)

mikael (484) | more than 2 years ago | (#38192874)

It doesn't matter what wavelength the photons are on. What matters is whether they are in enough numbers to cause physical damage. Sitting next to a hot electric fire for long enough is going to cause burning as much as touching a heating element.

Re:Next mod... (0)

Anonymous Coward | more than 2 years ago | (#38193144)

Or jam other peoples body scanners

The Future (2)

masternerdguy (2468142) | more than 2 years ago | (#38191284)

What can I do with 30 GiB/s? I'm trying to figure that out, give me some ideas.

Re:The Future (3, Funny)

mwfischer (1919758) | more than 2 years ago | (#38191320)

Run Windows Update and be done in about 15 minutes.

Re:The Future (0)

andreicristianpetcu (1964402) | more than 2 years ago | (#38191388)

15 minutes because of all the restarts I presume :)

Re:The Future (-1)

Anonymous Coward | more than 2 years ago | (#38191424)

You mean the one restart that takes a minute and a half on Windows 7?

Re:The Future (4, Funny)

0123456 (636235) | more than 2 years ago | (#38191502)

You mean the one restart that takes a minute and a half on Windows 7?

Followed by thirteen and a half minutes for all the crapware to start up after you log in.

Re:The Future (5, Funny)

Anonymous Coward | more than 2 years ago | (#38191350)

Cook chicken, most likely

Re:The Future (0)

Anonymous Coward | more than 2 years ago | (#38191354)

Wireless docking for your mobile device, when combined with inductive power. No more cables.

Re:The Future (3, Funny)

maeka (518272) | more than 2 years ago | (#38191874)

Wireless docking for your mobile device, when combined with inductive power. No more cables.

You going to rectify that?

Re:The Future (0)

Moheeheeko (1682914) | more than 2 years ago | (#38191386)

Download THE INTERNET.

....on second thought, no. Nobody should have that much porn.

Re:The Future (0)

Anonymous Coward | more than 2 years ago | (#38191430)

shame on you! there's no such thing as too much porn!

Re:The Future (0)

Anonymous Coward | more than 2 years ago | (#38191460)

You could go online and educate yourself about stuff like... GiB vs. Gbps.

Moron.

Re:The Future (0)

Anonymous Coward | more than 2 years ago | (#38191506)

very high definition video fed to a surgeon, very complicated signal from surgeon to on site robot that will do the work. etc

Re:The Future (2)

Lennie (16154) | more than 2 years ago | (#38192778)

Somehow I have the feeling it might be a bad idea to be operated on by a robot which is connected over wireless.

Most operations like that happen on an operation table in an operating room I would imagine, probably not the place where wireless is needed.

Re:The Future (1)

newsman220 (1928648) | more than 2 years ago | (#38191598)

Media. I work for a company that makes video editing systems, and 30GiB/s would be great when you're dealing with multiple streams of media at 225Mb/s or higher off a shared storage solution.

Re:The Future (5, Interesting)

Anonymous Coward | more than 2 years ago | (#38191656)

They said the same about broadband: "What could anyone possibly do with 20mbps? They barely use the 56k we give them!"

Give them the bandwidth - they'll find a good use for it. I can see it being very useful in a small/medium server room - 30Gbps makes it a competitive LAN system. Having a bunch of wireless cards would be much easier than running all that cable, even if some manual aiming and orientation of antennas is necessary.

I also imagine "the cloud" would benefit from this - even 1.5gbps is basically SATA speeds. Latency is higher, but the potential throughput gains are impressive. That may make it possible for "local storage" to be "operating system and cloud sync software", with everything being server-side somewhere. You and I may not join in (I don't like the privacy most of the cloud has), but many people don't give a shit about that.

Gaming might also benefit. Current online gaming depends a lot on synchronizing things, then letting the clients do a lot of the calculation. Updating the position of falling objects is almost always client-side, with the server checking every once in a while. It's a major headache, code-wise. With a suitably massive pipe, it becomes unnecessary - just send the coordinates every frame.

Or it makes video streaming work properly. Dealing with current streaming is rough on networks, as it needs to get there quickly. 30gbps to the home, and you can download an entire blu-ray, uncompressed, in two seconds. Latency can be looser - nobody's going to complain if it takes three seconds instead of two. There was an article on /. about that a couple months back.

Re:The Future (2)

Lennie (16154) | more than 2 years ago | (#38192862)

A lot of systems already support 10 Gbps Ethernet on UTP and fibre. 40 and 100 Gbps Ethernet is coming.

At 10 Gbps, iSCSI is already faster, cheaper and even lower latency than most 8 Gbps FibreChannel solutions, pushing FibreChannel even more into the highend niche markets it already is.

After the fairly new SATA 6 Gbit/s, it looks like SATA Express is will be connected directly to the PCI Express bus without needing a SATA controller.

This 30 Gbps wireless stuff is probably only useful for point-to-point and short ranges.

Re:The Future (1)

gman003 (1693318) | more than 2 years ago | (#38193004)

Yes, there's already 10+Gbps ethernet stuff. But that's honestly overkill for a lot of small/medium businesses' servers. Even 10Gbps is sort of overkill going to an Exchange server for 100 people. Few companies would pay extra to get 100GE to everything unless it actually benefits something.

Many companies, however, would pay a little extra to cut down on cable nests. Easier maintenance, easier expandability... those all serve business purposes. Bosses like to hear "this investment will cost $X, and save us $Y per year in reduced downtime as well as making us more agile at deploying new servers".

Re:The Future (0)

Anonymous Coward | more than 2 years ago | (#38191756)

What can I do with 30 GiB/s? I'm trying to figure that out, give me some ideas.

Bitch about how slow all your pirated movie torrents^W^W^W perfectly legal and morally innocent torrents of files that completely and purely coincidentally just happen to contain content which evil, evil, evil, evil, evil corporations want to make money with (which is in and of itself immoral and wrong) are going? I mean, the faster your connection is, the more authority you have to bitch about things. It's the internet way!

Re:The Future (4, Informative)

poetmatt (793785) | more than 2 years ago | (#38192102)

apparently nothing, because higher frequencies have horrible ranges. This stuff might work at ridiculously short range, but also won't be able to penetrate through anything which would enable it to work anywhere significant. Look at how tough even the 2.4ghz stuff like wireless devices can barely even penetrate a few walls, and now we're talking terahertz?

Long story short, nothing, because this product will never even give you 1.5Gbps.

Re:The Future (0)

Anonymous Coward | more than 2 years ago | (#38192180)

That wireless connection is faster than the hard drive I'm currently using.

Re:The Future (1)

sexconker (1179573) | more than 2 years ago | (#38192424)

What can I do with 30 GiB/s? I'm trying to figure that out, give me some ideas.

Nothing, because a "GiB" is not a thing.
1 GB is 1073741824 Bytes. It always has been, and it always will be.
Note that the "G" is not an SI scalar. No one ever said it was, and there's no reason it needs to be.
Note that there is never any confusion because you always see the G right next to the B. Indeed, there is no "K", "M", "G", etc.; there is a "KB", "Kb", and so on.
Note that calling 1 GB 1000000000 Bytes and 1 "GiB" 1073741824 Bytes - the proposed solution to the ambiguity - is what actually causes the ambiguity.
Note that the SI units, prefixes, etc. themselves have all sorts of ambiguity built in. T is Tesla. Or is it tera? K is Kelvin, or is it kilo? Gy is Giga...something? Oh no, it's just grays! And that's being generous - if you look at practical usage, where people and fields use units and variables of their own, or don't always use the proper case (or its use is indistinguishable), it's far worse. And then there's the mass fraction. Yup, kg/kg. The symbol for this unit? 1. That's right. The digit 1. Anytime you divide a mass by a mass you better add a superfluous 1 in there otherwise you're not compliant with the SI quackery!

It's "flammable" and "non-flammable" all over again. These are not words. These have been thrust upon the language like a /.er on a Yoda Fleshlight. The correct words are "inflammable" and "non-inflammable". The addition of "flammable" and "non-flammable" adds ambiguity and confusion where there was none. It has also killed people.

Neither of these are instances of language "evolving", so please kindly fuck off before you post that horse shit. The sole purpose of language is communication. When you introduce ambiguity and confusion, you are damaging the language.

Nude Sunnies ! (0)

Anonymous Coward | more than 2 years ago | (#38191296)

5 $ for the chip 10 $ for the circuitry and layout 10 $ for the HUD mounted in the sunglasses seeing every fat slob jump out of his skin - priceless! ("Terahertz waves can not only see through clothing, but can also penetrate a few millimeters of skin."

Re:Nude Sunnies ! (0)

Anonymous Coward | more than 2 years ago | (#38191716)

10 $ for the HUD mounted in the sunglasses seeing every fat slob jump out of his skin

X-Ray glasses, and fat slobs are what you use them on? Well, whatever floats your boat, I guess.

Doesnt matter (5, Funny)

Moheeheeko (1682914) | more than 2 years ago | (#38191342)

ISPs will still throttle your ass to 55 Mbps

Re:Doesnt matter (0)

bmo (77928) | more than 2 years ago | (#38191440)

I think you're not pessimistic enough.

I don't think the ISPs will stop until we're back to dialup speeds.

--
BMO

Re:Doesnt matter (1)

ifrag (984323) | more than 2 years ago | (#38192980)

ISPs will still throttle your ass to 55 Mbps

I'd be quite happy if I was only getting throttled down to 55 Mbps on downstream. For Comcast the 50 Mbps plan is almost the most extreme one you can get. Think I get throttled all the way down to something like 10/1.

Re:Doesnt matter (0)

Anonymous Coward | more than 2 years ago | (#38193172)

... on a 30 GIGABYTE plan you would be happy with getting throttled to 55 MEGABYTES?

you would pay, without complaint, for getting throttled down to 0.18% of what you pay for?

you sir, are everything wrong with this society.

Getting tired of this.... (1, Insightful)

JustAnotherIdiot (1980292) | more than 2 years ago | (#38191406)

We cured cancer! The cure will be out in a few years...
We solved the energy crisis! It'll be out in a few years...
And now this! They'll be out in a few years...
You know what? While we're at it, lets say we'll have mind reading devices that make a mouse and keyboard obsolete in a few years too.

Re:Getting tired of this.... (4, Interesting)

timeOday (582209) | more than 2 years ago | (#38191634)

30 years ago we were still paying $1.50 per minute to make international calls and you weren't allowed to plug a modulator/demodulator (aka "modem") into your phone line. 10 years ago, email was considered a high-bandwidth application for cellphones. 5 years ago the idea of widespread video streaming over the Internet was commonly dismissed on slashdot as infeasible.

To complain that network technology never really improves is the height of absurdity.

Despite what the blurb says, this technology may finally be a good competitor for wired ethernet to the home. It's directional, so it doesn't have to be shared among a huge number of houses, and at $5/pop you can build a "disco-ball" covered with them to blanket an area. It won't penetrate walls well, but will penetrate adverse weather better than laser light.

Short of replacing Comcast, at least we can finally have a wireless HDMI "cable" that is affordable, so I can hook any number of terminals to a computer without having to bunch them all together.

Re:Getting tired of this.... (0)

Anonymous Coward | more than 2 years ago | (#38191692)

No you are just deluding yourself and your examples are too poor to be usable as your defending argument.

Re:Getting tired of this.... (1)

JustAnotherIdiot (1980292) | more than 2 years ago | (#38191726)

I wasn't complaining it never improves, I was complaining that I'm tired of reading slashdot articles that post a time of release as "in a few years"

Re:Getting tired of this.... (3, Funny)

Anonymous Coward | more than 2 years ago | (#38192158)

We should be able to implement a filter that stops these kinds of posts within a few years.

Re:Getting tired of this.... (1)

timeOday (582209) | more than 2 years ago | (#38192238)

I was complaining that I'm tired of reading slashdot articles that post a time of release as "in a few years"

But I think people are mistaken for not seeing the link between these types of announcements, and the incremental increases in capability and reductions in price that we are accustomed to seeing in new products. It's so easy to just assume Moore's "Law" will continue to hold, likewise for hard drive density, networking, and other applications such as medical imaging, as if that just comes naturally for free, and as if all these advances in physics, material science, and manufacturing are just games people play off to the side that never amount to anything. It's not true.

Re:Getting tired of this.... (1)

Crudely_Indecent (739699) | more than 2 years ago | (#38191718)

You could always do the research yourself, fund it, fund the prototype phase, ramp up the manufacturing facilities and then bribe the equipment manufacturers to immediately use your new hardware in their current product lines.

That sounds do-able. Would you be happy with that kind of immediacy?

Re:Getting tired of this.... (1)

JustAnotherIdiot (1980292) | more than 2 years ago | (#38191758)

I'm not asking for immediacy either, It's more skepticism. I'm constantly reading articles that say "Oh, we'll have it in a few years..."

Re:Getting tired of this.... (0)

Anonymous Coward | more than 2 years ago | (#38191868)

You know what? While we're at it, lets say we'll have mind reading devices that make a mouse and keyboard obsolete in a few years too.

Sure, stop living on the scraps of progress cast your way and do it yourself you fucking beggar.

NO GHZ ?? AND WHO PISSED IN MY BONG WATER ?? (0)

Anonymous Coward | more than 2 years ago | (#38191428)

When it gets to GHz do let me know, so I can dowmload my month's ration in 1 minute. See here, and listen to me later. More speed is useless if I have a cap that I reach using that speed, so what's the point?

Re:NO GHZ ?? AND WHO PISSED IN MY BONG WATER ?? (0)

X0563511 (793323) | more than 2 years ago | (#38191472)

WAN is not everything. What about communications between your devices, eh?

Seriously... (1)

Anonymous Coward | more than 2 years ago | (#38191454)

"...it's more like a laser than a signal..."

A laser is a signal

Re:Seriously... (2, Funny)

Lord Lode (1290856) | more than 2 years ago | (#38191642)

It isn't if you attach it to sharks. Then, instead, it's deadly.

do not look at shark with remaining eye (1)

Thud457 (234763) | more than 2 years ago | (#38191794)

...it's more like a laser than a signal...

A laser is a signal

Any sufficiently powerful laser is a signal that you want something destroyed, Mr Bond.

Any insufficiently powerful laser can still make a amusing cat toy.

Step into the Tear o' Hurts scanner citizen (2)

Nadaka (224565) | more than 2 years ago | (#38191500)

Step into the Tear o' Hurts scanner citizen, if you choose not to you may instead choose to be violated by the TSA sanctioned probulation team currently on work release from a local for profit penitentiary.

House "wiring"? (0)

Anonymous Coward | more than 2 years ago | (#38191534)

Can this stuff go through walls and floors? Could I use a couple of directional antennas to run "wiring" up to the second and third floors of my house where I have no ethernet?

Run it by a RF EE next time (4, Interesting)

vlm (69642) | more than 2 years ago | (#38191542)

Run it by a RF EE next time, or at least an advanced ham radio guy.

using a chip and antenna that's just two centimeters long

a stark comparison to current terahertz gear that's both large and expensive.

with a submillimeter wavelength

First of all its hard from a RF perspective to make stuff thats more than a 1/4 wavelength long. Obviously possible, but much harder. For example, I'm working on a K band transverter and one nightmare is standard SMA connectors resonate at 18 GHz or so, making them quite exciting to use. Yes I already know about the expensive and complicated and almost but not quite SMA compatible connectors I can use. Aside from connector and feedline issues, Its actually EASIER to make small stuff than large stuff at high frequencies / small wavelengths. Cable attenuation makes you put the whole RF works at the dish feedpoint above 50 GHz or so, if you want decent performance. The smaller it is, the lighter it is, more or less, making the mechanical engineering job simpler. Its not like 50 GHz amplifier dies are currently the size of dinner plates and will someday be the size of rice grains... they're already tiny. Ditto this chip. Also the silicon is cheap, the tools are expensive. A new ultrasonic wirebond machine must be worth, i donno, tens to hundreds of thousands of cheap MMIC dies? When you buy MMIC dies, its not like they're blowing lots of money on packaging... And thats before you hire the rare skilled labor to set up and operate and maintain the already expensive wire bonder. Wirebonding zero ohm resistors wouldn't really change the overall cost vs wirebonding some fancy dies because of the huge fixed and variable costs of the technology, so changing the die cost from ten dollars to ten cents isn't gonna help if the overall project cost due to R+D and manufacturing and test gear averages out to ten grand per active device...

Secondly complete THZ systems are large and remain large and will probably always be "large". The internal chips are already small, and, frankly, relatively cheap. Antenna cannot be magically shrunk for same performance. Support gear like bias and main power regulators don't "know" they're powering microwave gear and should therefore be shrinking at a microwave pace. DSP processors don't "know" they're connected to a shrinking MMIC die and therefore they should be shrinking at a microwave pace. Support gear does shrink over time at the rate of normal support gear shrinkage, which isn't that fast. For example, not much has changed in the world of linear voltage regulators in the last 30 years... somewhat lower current references, MOS pass transistors instead of bipolar means lower voltage drop, um... thats about it?

Re:Run it by a RF EE next time (1)

MattskEE (925706) | more than 2 years ago | (#38192418)

Although the article claims to be talking about a silicon *transceiver* running at *300+GHz*, the graphics included in the article just have a planar horn antenna and a diode on an InP substrate all connected up to a SMA connector. A bit disappointing to be honest. No mention of whether they're using the diode as a detector or mixer (or both), but the pieces they are talking about appear to be a long ways away from an actual communication system.

One of the big problems faced in reality will be getting enough power to overcome the high losses at THz frequencies, particularly if they are eschewing LNA's and PA's at the front end and using the diodes for up-/down-conversion. Given the simplicity of the front-end it will require a lot more complexity and high-power in the back-end circuitry which they make no mention of solving. And if they are using some high-harmonic mixing with that diode then they're probably not going to meet regulatory emission requirements using just the antenna structure to filter out radiation of the spurious mixing products.

Re:Run it by a RF EE next time (1)

Matheus (586080) | more than 2 years ago | (#38192488)

All that being said... if you would please just RTFS you'll get the following little tidbit: "using a chip and antenna that's just two centimeters long". Note the second half of that and-combo and your initial problem of "Antenna cannot be magically shrunk for same performance" seems to be what they've solved.

IANAHFCD but I apparently can read...

The Future (0)

Anonymous Coward | more than 2 years ago | (#38191552)

X-Ray emulating apps anyone?
"Check if your bone is broken with our new app!"

An easy choice (0)

Anonymous Coward | more than 2 years ago | (#38191566)

High speed interwebed devices > Radiation

What about saturation? (4, Insightful)

AngryDeuce (2205124) | more than 2 years ago | (#38191584)

All the wireless tech in the world doesn't seem to be able to stand up against saturation in the band.

I say this, of course, as someone who lives in an apartment complex of 100's of units, all in close enough proximity that Wireless-N signals can be picked up pretty much anywhere in the complex from any users apartment. I had to forego wireless entirely and hard wire everything because every band was completely saturated with dozens of wireless networks. With the smart-switching shit that automatically looks for clean channels it's even worse; I've taken to illustrating the problem to friends at parties with the wifi scanner app on my phone, we all get a good laugh watching 10 networks bounce up and down the band constantly "Channel 1 is clean, quick, switch to channel 1! Shit, 9 other networks came with me...look, channel 3 is clean, quick, switch to channel 3! Fuck, they're following me! Channel 7 is clean, quick, switch to channel 7!!" all day long.

The wireless band is becoming way over saturated. Now that we have cars with built in hotspots it's going to get even worse. We need some sort of fundamental shift in the way we do wireless networking, either that, or we need to greatly expand the band and the range between channels so that 30 devices can cohabitate the same frequency range without completely fucking up throughput.

Re:What about saturation? (2)

Arrepiadd (688829) | more than 2 years ago | (#38191806)

As it's mentioned in the summary, the Terahertz frequencies are very directional, unlike the typical GHz stuff of wireless networks. So, instead of broadcasting for all the neighborhood you are transmitting more on a point to point fashion. Saturation is almost irrelevant in this scenario (as long as the signal dies off within the solar system).

Re:What about saturation? (1)

AngryDeuce (2205124) | more than 2 years ago | (#38192088)

Great, when there's one transmitter focused at one receiver. What happens when there's 20 transmitters sending to 20 receivers all within close proximity to each other? Wifi worked just fine for me 5 years ago when there was only as handful of people using it in my complex, now that everyone has wifi the service has become so degraded it's practically unusable for anyone that is trying to do more than surf the internet (and even that is a chore, requiring many page reloads sometimes to get the full page to load). Trying to transfer files, forget it, you might as well .rar it into a hundred pieces and email it.

The fact that we're making every damn thing wifi capable these days is only going to exacerbate the problem. Simply switching to a new band isn't going to solve the problem, it just creates a new saturation point. Similar to the IPv4 to IPv6 transition, we need to come up with a solution that allows for a much, much wider frequency range with dozens of new 'channels' to handle all the traffic, along with routers that can actually talk to each other and negotiate. Rather than having 15 routers all chasing each other up and down the spectrum all day, we need routers that say "Okay, router A, you can have channel 1, router B can have channel 2..." rather than "ZOMG CHANNEL 1 IS CLEAN EVERYBODY RUUUUUUUUUN!!!!!!"

Re:What about saturation? (0)

Anonymous Coward | more than 2 years ago | (#38192606)

Great, when there's one transmitter focused at one receiver. What happens when there's 20 transmitters sending to 20 receivers all within close proximity to each other?

What part of highly directional did you not understand?

Look at the image to the right in this wikipedia page, it should give you a pretty good idea of how THz radio waves behaves. [wikipedia.org]
An example of communication in the THz range is a typical traffic intersection where you have a set of broadcasting devices (Traffic lights) pointed in each direction and multiple receiveres (Drivers) for each broadcasting unit.
Not only is each direction shielded from the others with a simple piece of plastic but it is also possible for the receiver to obtain a clear signal even if several broadcaster sends a continous signal at the same time.

Re:What about saturation? (1)

AngryDeuce (2205124) | more than 2 years ago | (#38192900)

It still doesn't solve the problem. It may currently help, but eventually it's going to have the same problems of saturation no matter how directional it is.

Finding new bands to saturate is not going to help the problem. We need a much wider band with many more discrete channels and smarter routers that are able to cooperate among themselves and share the bands in the most effective, efficient ways possible. That in itself would go a long way towards solving these saturation problems and there would be plenty of space available for everyone.

Re:What about saturation? (0)

Anonymous Coward | more than 2 years ago | (#38191814)

Actually, this would _help_ with that. Terahertz radiation doesn't penetrate walls very well, so it would be ideal for LANs in a crowded building. You might have problems getting from room A to B, but your next door neighbor isn't going to see your access point.

Re:What about saturation? (0)

Anonymous Coward | more than 2 years ago | (#38191962)

Part of the problem might be that you're using non-isolated channels - 3 and 7. Channels 1, 6 and 11 are the only 3 non-overlapping channels on 2.4Ghz wireless networks. Channel 3 overlaps heavily with channels 1-5. Handy visual: http://en.wikipedia.org/wiki/File:2.4_GHz_Wi-Fi_channels_(802.11g_WLAN).svg

I suggest switching to a 5Ghz wireless network. Less penetration through walls and a much larger selection of non-overlapping channels. 802.11a/n is the way to go.

Re:What about saturation? (2)

joe_kull (238178) | more than 2 years ago | (#38192004)

I know it's traditional to skip reading the article, but the summary points out that this will be a directional-only signal. Directional signals generally don't have saturation problems, because they propagate (to simplify) in cones rather than spheres.

Re:What about saturation? (1)

AngryDeuce (2205124) | more than 2 years ago | (#38192130)

I understand that, so what happens when there's 15 cones propagating right next to each other? You know, kinda like how traditional wifi has exploded to the point where every goddamn thing in the world is a hotspot now?

Re:What about saturation? (0)

Anonymous Coward | more than 2 years ago | (#38192312)

Did you try the 5Ghz spectrum?

Re:What about saturation? (1)

jader3rd (2222716) | more than 2 years ago | (#38192552)

I agree. I had to recently run some ethernet cable around my apartment because I couldn't get a reliable enough connection. I have one neighbor who must have felt like they weren't getting a strong enough signal and must have bought some equipment to boost their signal because I could pick up their signal stronger than mine at any point in my place. Ever since then we've just gotten used to the fact that we can't step on the small bump in the carpet where I didn't have a better place to run the cable, but we haven't had connection issues.

A non-issue with THz! (1)

Vario (120611) | more than 2 years ago | (#38192850)

In short: THz penetrates your T-shirt (airport scanners) but not any thin drywall.

Roughly speaking for electromagnetic waves the higher the frequency the more light-like the radiation becomes. THz is close to infrared light, it will not penetrate much but can be used to transmit a lot of data because you can modulate it with a much higher frequency than standard 2.4 GHz wireless LAN. This comes at a price though, if a person walks through the line-of-sight between your notebook and the hypothetical THz wireless access point the signal will be cut off immediately. So it is a nice idea to replace HDMI cables or similar connections but might not work so well as a WLAN replacement.

There are also people working on modulating your LED lighting to transmit data without cables (OFDM Visible Light Wireless Communication Based on White LEDs [jacobs-university.de] ) and this is a nice example that in the future we might use the whole available spectrum to transmit information and saturation will not be a big problem anymore.

Thin, think, think.... (0)

Anonymous Coward | more than 2 years ago | (#38191592)

Somebody should tell these silicon fellas that radio waves above 300GHZ are strongly attenuated by things like air and water vapor in the air.

Re:Thin, think, think.... (1)

Shompol (1690084) | more than 2 years ago | (#38192450)

300GHZ = 3*10^11 Hz
Speed of light / 3*10^11 Hz = 1 mm wavelength, which should have no problem bypassing particles less than 0.5 mm in diameter.
By comparison, visible light is 400-700 nm [wikipedia.org] , that's 4/10000 mm, so fog and rain that limit our field of vision should pose little to no problems for a 300GHZ wave.

good news everyone! (1)

nimbius (983462) | more than 2 years ago | (#38191660)

here in the future the 30Gbps wireless service is all seeing, all knowing, and spans across the city uninterrupted with a lemony fresh scent.

Cancers however continue to elude us. We've taken to naming them after impressive sounding former presidents, or basing cartoon characters upon their loose interpretation. Incidentally, if you come across any historic manuscripts related to airport scanner safety, we would be quite interested.

Re:good news everyone! (1)

blueg3 (192743) | more than 2 years ago | (#38192166)

This is still below the ionization threshold, and so will not cause cancer at any appreciable rate.

Re:good news everyone! (1)

Instine (963303) | more than 2 years ago | (#38192540)

"and so will not cause cancer at any appreciable rate."
But might it detect it?...

Re:good news everyone! (1)

blueg3 (192743) | more than 2 years ago | (#38192864)

The imaging depth for THz is shallow enough that it could only theoretically detect skin cancers. Whether or not that's even reasonable is outside my expertise, though.

meh (0)

Anonymous Coward | more than 2 years ago | (#38191706)

While your provider still feeds you 2-3Gbps, your wireless connection to your router will be a mighty 30Gbps.

mmmm chicken (0)

Anonymous Coward | more than 2 years ago | (#38191850)

I look forward to using this to expand my business.

  - anonymous fried "chicken" street vendor

Satellite Wireless Router (1)

sgt scrub (869860) | more than 2 years ago | (#38191866)

This could open up cheap land to space communication. This begs the question, "What is the cheapest way to send a home built satellite into a geosynchronous orbit"?

Re:Satellite Wireless Router (1)

INeededALogin (771371) | more than 2 years ago | (#38192146)

This could open up cheap land to space communication.

No... if you read the article you will see that these waves are affected by radiation. Last time I checked, space has a lot of radiation.

Hope you like rain fade (1)

jandrese (485) | more than 2 years ago | (#38191960)

The problem with high frequency wireless networking is that more and more stuff becomes opaque as you increase the frequency. For Terahertz networks you're pretty much going to require a clear line of sight between you and the receiver. The directionality thing will be a big problem too, I'm sure some of us can remember setting up IR networks a few years ago (when laptops still had IR ports on them). Unless you're talking about fixed installations, Line of Sight is a big hurdle to adoption.

In short: there are serious problems with this gear that will limit its applicability. There is a market for fixed line of sight networks like this, emergency response situations where people set up temporary tents but need to communicate for instance. You stick a pole in the ground at each tent, tape an antenna on the top, and point them at one another. That's a pretty esoteric use case however. Generally if you have fixed installations, it makes sense to just dig a trench (or using the existing infrastructure!) to run a wired network instead, that way it won't go down in the rain or fog or when a bird tries to perch on your antenna pole.

Terahertz is not very practical (5, Informative)

NixieBunny (859050) | more than 2 years ago | (#38192200)

This article is basically nonsense. I work with folks who actually make terahertz radio equipment for radio astronomy. It seems like the last place in the spectrum you'd go to for anything practical. The technology is very primitive, since there has been little application for it, since the signals are quickly absorbed by water vapor in the atmosphere. My coworkers are currently in Antarctica to do some astronomy, because there's very little water in the air there.

A stable local oscillator that puts out any useful amount of terahertz power is very difficult to make. You are lucky to get a few microwatts. The signals aren't quite as directional as a laser, but they're too directional to be of much use for the wireless networking that we are familiar with.

There are optical ways of making signals at terahertz frequencies, which may hold more promise, but they're being used in only a few exotic applications, such as the ALMA interferometer array in Chile.

Terahertz waves - can I see them? (0)

Anonymous Coward | more than 2 years ago | (#38192202)

Serious question: Of course we're talking of about up to 3THz waves, visible light is much shorter in wavelength, starting from 385Thz (according to wikipedia). But assuming we'd have a radio transmitter of say 500Thz (the color green), would the "antenna" light up?
Btw I just realized we already have cheap terahertz transmitters with integrated antennas - they're called LEDs.

more like a laser than a signal (0)

Anonymous Coward | more than 2 years ago | (#38192216)

I'm stunned. Editors, do you even read what you publish? Are you so clueless that you don't see how ridiculous this statement is? The readership at Slashdot is just of so much higher standards than its editors, it seems.

Blog of blog of blog of ... - finding real info (1)

Animats (122034) | more than 2 years ago | (#38192384)

Three ad-heavy blogs deep, the best I'm able to find is a brief note in Electronics (AU) [electronicsnews.com.au] . It's not even clear if the device pictured is an emitter or a detector.

Terahertz RF is essentially line of sight, and has roughly the propagation characteristics of light. This is not going to be useful for WiFi or cellular telephony. Imaging, though, may work. Here's a good paper [okstate.edu] on the subject. In the terahertz range, both RF and optical techniques are used; there are both antennas and lenses. The high end of the terahertz range overlaps the low end of infra-red.

Re:Blog of blog of blog of ... - finding real info (1)

MightyMartian (840721) | more than 2 years ago | (#38192486)

Definitely could be useful for line-of-site backbones, though. Years ago I worked for a guy and we set up some of proprietary 2.4ghz bridges for just that purpose.

Wireless (1)

tesdalld (2428496) | more than 2 years ago | (#38192842)

So when is the wifi going to melt the atmosphere? i would think this is going to heat up the atmosphere and make things worse... no?
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