Japanese Researchers Transmit 3Gbps Using Terahertz Frequencies

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Japanese Researchers Transmit 3Gbps Using Terahertz Frequencies

Posted by samzenpus on Wednesday May 16, 2012 @07:15AM from the greased-lightning dept.

MrSeb writes "Researchers at the Tokyo Institute of Technology have developed a new wireless transmission system that works above all currently regulated spectrum frequencies. The new system works at the range of 300GHz to 3THz (terahertz), which is the Far Infrared (FIR) frequencies of the infrared spectrum. That spectrum is currently totally unregulated by any country or standards organization in the world, making it ripe for development of new technologies. So far the Japanese researchers have transmitted data at 3Gbps, but in theory speeds of up to 100Gbps should be possible."

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Gamma Rays by Sigvatr · 2012-05-16 07:17 · Score: 5, Funny

How soon will it be until Japan begins transmitting gamma rays?
1. Re:Gamma Rays by Anonymous Coward · 2012-05-16 07:33 · Score: 0
  
  Without gamma rays, no mothra would be possibre. Since mothra arready up in sky, they already do gamma ray data transmission, you dumb American.
  
  Ah hahahaha. AH HAHAHAHA.
  
  ???
2. Re:Gamma Rays by Anonymous Coward · 2012-05-16 09:34 · Score: 0
  
  don't make me angry. you wouldn't like me when i'm angry.
3. Re:Gamma Rays by Anonymous Coward · 2012-05-16 10:27 · Score: 1
  
  Dude, are you high?
4. Re:Gamma Rays by Anonymous Coward · 2012-05-16 20:49 · Score: 0
  
  Tokio Institute of Technology. Cool. I would also love to work at the "TIT".
5. Re:Gamma Rays by Douglas+Goodall · 2012-05-17 05:11 · Score: 1
  
  It is true, but Mothra also has other emitted energies that have reconstituted Godzilla, and also emits an energy that is used by the twin fairies as a transport beam. I would think DARPA would want to spend some money researching that. /s Doug
6. Re:Gamma Rays by Anonymous Coward · 2012-05-17 14:07 · Score: 0
  
  Isn't that what they are doing at Fukashima?
Hmmm... by mcgrew · 2012-05-16 07:19 · Score: 3, Insightful

Infrared? Not exactly wi-fi. You'd have to be in the same room as the router for this to work. I don't see many practical applications.

--
Free Martian Whores!
1. Re:Hmmm... by MacTO · 2012-05-16 07:24 · Score: 4, Interesting
  
  Different wavelengths of IR have different properties. Indeed the BBC article notes: "as terahertz waves penetrate many materials as effectively as X-rays".
2. Re:Hmmm... by Anonymous Coward · 2012-05-16 07:24 · Score: 0
  
  That doesn't really matter because you are stupid.
  No you are... He/She is right. Turns out IR doesn't go through walls too well.
3. Re:Hmmm... by what2123 · 2012-05-16 07:26 · Score: 0
  
  Some days I wish we had a mod for "Lulz."
4. Re:Hmmm... by heypete · 2012-05-16 07:26 · Score: 3, Interesting
  
  Infrared? Not exactly wi-fi. You'd have to be in the same room as the router for this to work. I don't see many practical applications.
  It sounds actually quite reasonable for private wireless networks: put a transceiver on the ceiling or an elevated part of the wall and provide high-speed access to network devices in that room.
  Assuming the waves wouldn't penetrate ordinary building materials (though the wikipedia suggests that some building materials are not reasonably opaque to these waves) then one could have the convenience of a wireless network without the security risks involved with longer-range radio waves that can be picked up at much greater distances.
5. Re:Hmmm... by redfox2012 · 2012-05-16 07:38 · Score: 1
  
  You'd have to be in the same room as the router for this to work.
  Sounds ideal, I'll have one in each classroom please!
6. Re:Hmmm... by bws111 · 2012-05-16 07:43 · Score: 1
  
  But isn't the point of using x-rays for diagnostic purposes is that they only penetrate stuff that isn't dense? Things like walls tend to be dense.
7. Re:Hmmm... by QuantumRiff · 2012-05-16 07:52 · Score: 2
  
  But could be ideal for a wireless back-haul, where you are currently using microwave with line of site..
  
  --
  
  What are we going to do tonight Brain?
8. Re:Hmmm... by h4rr4r · 2012-05-16 07:54 · Score: 1
  
  Walls are dense? Where?
  The average wall is two half inch think drywall sheets and air. External walls have insulation, but that stuff is designed not to be very dense. Studs are dense, but they are only every 16 or so inches.
9. Re:Hmmm... by Anonymous Coward · 2012-05-16 07:56 · Score: 0
  
  Infrared? ...I don't see many practical applications.
  Channel surfing really fast.
10. Re:Hmmm... by Eponymous+Hero · 2012-05-16 07:58 · Score: 0
  
  cuz Funny just doesn't say the same thing?
  
  --
  insensitive clod overlords obligatory xkcd car analogy russian reversals whoosh pedant fanbois ftfy in 3...2...1..PROFIT
11. Re:Hmmm... by Kelerei · 2012-05-16 08:05 · Score: 1
  
  Walls are dense? Where?
  The average wall is two half inch think drywall sheets and air. External walls have insulation, but that stuff is designed not to be very dense. Studs are dense, but they are only every 16 or so inches.
  Perhaps in your part of the world, the average wall is like that -- but that doesn't mean that that's applicable throughout the rest of the world. Over here (Cape Town), stuff generally gets built with bricks, and the walls of my apartment are of sufficient thickness that my Desire HD has an extremely hard time picking up the wireless signal from an adjacent room.
12. Re:Hmmm... by Anonymous Coward · 2012-05-16 08:12 · Score: 0
  
  So, not very well then.
13. Re:Hmmm... by Anonymous Coward · 2012-05-16 08:20 · Score: 0
  
  my apartment are of sufficient thickness that my Desire HD has an extremely hard time picking up the wireless signal from an adjacent room.
  Apartments are frequently made with sound insolation on the interior walls. Some of these materials are highly reflective and/or absorbant to a wide range of frequencies. It sounds like this is the material in your walls. Its not so much that your walls are dense, its that they are built with material designed to stop propagation of various frequencies.
  If you care, in an apartment setting, this also has advantages as it reduces the overall noise level at apartments and helps ensure signal propagation within the unit without flooding everyone else for a surrounding block. At many apartments, use of WIFI can be nearly impossible because so many AP's are in use with signal propagation spreading throughout the place.
14. Re:Hmmm... by h4rr4r · 2012-05-16 08:29 · Score: 1
  
  That's probably because you are holding the phone upside down from being so far south. Try flipping it over.
  Even interior walls are brick? That seems highly wasteful.
15. Re:Hmmm... by Anonymous Coward · 2012-05-16 08:32 · Score: 0
  
  Apartments are frequently made with sound insolation on the interior walls.
  Not, it appears, any in the area I live.
16. Re:Hmmm... by dissy · 2012-05-16 08:42 · Score: 2
  
  Infrared? Not exactly wi-fi. You'd have to be in the same room as the router for this to work. I don't see many practical applications.
  No terahertz is not exactly wifi. Both are blocked by thick metal for example, neither are blocked by wood glass or plastic.
  In fact the only things I know of that will block terahertz which wifi goes through are water and bone.
  If your walls are made of water or bone, then yes you will need to stay with gigahertz frequencies :P
17. Re:Hmmm... by hawguy · 2012-05-16 08:48 · Score: 2
  
  Infrared? Not exactly wi-fi. You'd have to be in the same room as the router for this to work. I don't see many practical applications.
  Then you haven't seen how much it costs to wire an office and provide network ports.... *and* keep it neat "Why do those wires have to come down the wall, why can't they go through the floor? Because I'd have to core through 8" of concrete to do that. Well, just do it, it's only money!" (then the same thing happens next year when the cubes are moved).
  If I could hang 4 or 6 of these off the ceiling to provide network coverage to a 40 person open office area, it could be a huge money (and headache) saver. Especially when the cubes are rearranged every year for "efficiency and productivity" (which in some years means squeezing more people into the same, other years it means less people with more space). Even if it means putting an antenna on top of the cube walls or overhead shelves it's still easier than running new wire.
  Wifi doesn't provide enough non-overlapping channels to provide good service to many users in a small area - especially when they are copying large media files to/from the corporate fileserver. But if 4 of these could each do 3gbit (with clients load balancing across them automatically), that's already more than the 4Gbit of aggregate bandwidth that this office area has now.
18. Re:Hmmm... by Anonymous Coward · 2012-05-16 08:51 · Score: 0
  
  For a nerd site there are lots of dumb asses on here...
19. Re:Hmmm... by Grishnakh · 2012-05-16 08:59 · Score: 1
  
  And if you're getting your routers with a government stimulus grant, you can buy top-of-the-line $22,000 Cisco routers for every single classroom too!
20. Re:Hmmm... by superdave80 · 2012-05-16 09:01 · Score: 1
  
  Thickness and density are two completely different things.
21. Re:Hmmm... by hawguy · 2012-05-16 09:05 · Score: 1
  
  That doesn't really matter because you are stupid.
  No you are... He/She is right. Turns out IR doesn't go through walls too well.
  I thought the stupid part was for not seeing any practical use for a 3Gbit wireless network that doesn't go through walls.
  My home computer is in the same room as my Wifi router. And my office computer is within line of sight of the nearest Wifi antenna. My TV, Bluray player and internet modem are all within line of sight, it would be nice to not have to wire them together so I could put the Bluray player next to the couch and have it wirelessly send video to the TV on the other side of the room, and have both able to connect to the internet modem. (ok, both the TV and Bluray player do 801.11g, but I can already buy an internet connection that's faster than that 801.11g - and I pick up interference from a lot of neighbors, I can literally see 37 other 802.11bg Wifi networks from my apartment, I'd be happy to have something with less wall penetration. I can only see 6 Wifi networks operating on 5Ghz, but that's probably more due to market penetration than lower 5Ghz wall penetration)
22. Re:Hmmm... by rev0lt · 2012-05-16 09:11 · Score: 0
  
  Funny is so late 90's. Kids this days...
23. Re:Hmmm... by Anonymous Coward · 2012-05-16 09:14 · Score: 0
  
  I think he means concrete, not brick. In The Netherlands most houses are made from concrete and as such most walls are also.
24. Re:Hmmm... by hawguy · 2012-05-16 09:24 · Score: 2
  
  The article has an even better application of a short-range wireless system that doesn't penetrate walls -- networking for servers in the datacenter. Currently I have a 6 node VMware cluster built from discrete 1U servers with about 60 network interconnects (including intra-cluster communications, but also connections to the core network and SAN network) Ok, so all are 1Gig and it would take a fraction of that in 10Gig connections and a blade center would help too, but the cluster was built before 10Gig was cost effective.
  100Gbit wireless sure would make the datacenter neater.
25. Re:Hmmm... by Ihmhi · 2012-05-16 09:50 · Score: 1
  
  Big tower with multiple IR lasers.
  Every roof has an IR receiver.
  We can already align satellite dishes just fine on our own. Now would my idea be any good for the city? Not really. But how about in a rural area where they have a lot of open space and LoS? Sure, the occasional passing goose might get blinded, but hey, free dinner if he crashes onto land!
  
  --
  Random Thoughts From A Diseased Mind (Not For Dummies)
26. Re:Hmmm... by Eponymous+Hero · 2012-05-16 09:51 · Score: 2
  
  diversity and taste. that's why there are more options for aesthetics than what purely pragmatic, utilitarian points of view have to offer. it turns out that people will design things all kinds of crazy ways with crazy materials just to stand apart, break the monotony, add value, or serve a particular purpose that is outside of average. yes, interior walls can be brick. in a lot of homes, in a lot of places. stop trying to excuse your assumptions by projecting your ignorance as insults, you look stupid. much more wasteful than interior brick walls is the electricity you used to make all these posts arguing about average wall density.
  
  --
  insensitive clod overlords obligatory xkcd car analogy russian reversals whoosh pedant fanbois ftfy in 3...2...1..PROFIT
27. Re:Hmmm... by Anonymous Coward · 2012-05-16 10:22 · Score: 0
  
  You're thinking about it wrong. Have you ever noticed that you can see through skin with a flashlight in a dark room? It's all about to what degree
28. Re:Hmmm... by lucmove · 2012-05-16 11:24 · Score: 0
  
  "Walls are dense? Where?"
  Must be an American.
29. Re:Hmmm... by Anonymous Coward · 2012-05-16 13:11 · Score: 0
  
  Resonance with DNA at the THz level results in potentially destroying DNA. More research appears to be needed, but localized emissions in this frequency range seem to be undesirable.
  If resonance does in fact occur, then in laymen terms, it means that DNA acts as an antenna and hence relatively small amount of energy will "boil" your DNA.
  http://www.technologyreview.com/blog/arxiv/24331/
  http://arxiv.org/abs/0910.5294
  
  Alexandrov and co have created a model to investigate how THz fields interact with double-stranded DNA and what they've found is remarkable. They say that although the forces generated are tiny, resonant effects allow THz waves to unzip double-stranded DNA, creating bubbles in the double strand that could significantly interfere with processes such as gene expression and DNA replication. That's a jaw dropping conclusion.
30. Re:Hmmm... by Anonymous Coward · 2012-05-16 14:52 · Score: 1
  
  Before modern insulation, double brick houses were cheaper in cold areas.
31. Re:Hmmm... by 0111+1110 · 2012-05-16 15:22 · Score: 1
  
  Also concrete construction is simply the norm in many countries. Stick frame construction is superior in terms of thermal insulation, but generally inferior in terms of sound transmission level. Stick frame construction would be quite a bit more expensive in countries that normally use concrete.
  
  --
  Quite an experience to live in fear, isn't it? That's what it is to be a slave.
32. Re:Hmmm... by 0111+1110 · 2012-05-16 15:29 · Score: 1
  
  Gosh. Stop the presses. They've created a model. I suppose actually aiming a Thz transmitter at some real DNA was far too much trouble. So much easier to to just write a C function that is absolutely 100% indistinguishable from real DNA.
  
  --
  Quite an experience to live in fear, isn't it? That's what it is to be a slave.
33. Re:Hmmm... by __aaltlg1547 · 2012-05-16 16:11 · Score: 1
  
  ...most of them being gases...
34. Re:Hmmm... by The+Master+Control+P · 2012-05-16 17:04 · Score: 2
  
  People like you who mock some idiotically shallow view of things you don't understand as a way of reinforcing your fragile ego inspire a mix of anger and pity in those of us who actually do research and design things.
  
  Has it ever occurred to you that maybe there's an actual reason they didn't "simply" aim a THz transmitter at some DNA? Like, "How do you observe what's being done to the DNA, in vitro, without damaging it?" Or, "getting the grants and building the apparatus and developing the techniques to do this would take years, possibly decades?" But of course it hasn't, because that would require you to stop being a snivelling ass and think for 30 seconds.
  
  And not only that, but seriously, what the fuck... Our JOBS are to be in a lab, staring at the screen, poking the deposition chamber, tweaking the laser table, all day, thinking about what we want to find out and how to find it out. Do you seriously think that whatever half-baked ideas floated through your head 10 seconds after reading a random comment on an Internet message board, on a topic you've probably never devoted a second of consideration to before in your life, are going to contain some brilliant insight that's going to leave us all dumbfounded?
  
  /rant
35. Re:Hmmm... by Chatterton · 2012-05-16 22:16 · Score: 1
  
  In north of france, buildings build after the second war are mostly build from red bricks. 2 to 3 bricks wide for structure walls and 1 brick wide for interior walls.
36. Re:Hmmm... by Anonymous Coward · 2012-05-16 23:37 · Score: 0
  
  Infrared? Not exactly wi-fi. You'd have to be in the same room as the router for this to work. I don't see many practical applications.
  It is not wise to strictly distinguish between the same thing with different properties. There is not strict line that says what radio frequencies can be used for.
  Radio, IR, visible light and UV are all the same thing.
37. Re:Hmmm... by Anonymous Coward · 2012-05-17 00:16 · Score: 0
  
  i'm assuming this should read:
  "The average wall in america is two half inch think drywall sheets and air. External walls have insulation, but that stuff is designed not to be very dense. Studs are dense, but they are only every 16 or so inches."
  not everyone builds their house out of sticks.
38. Re:Hmmm... by s0nicfreak · 2012-05-17 02:36 · Score: 1
  
  Single-room apartments are common in Japan. And though I have a multi-room house with computers in other rooms, my main computer and router are in the same room.
39. Re:Hmmm... by Anonymous Coward · 2012-05-17 11:38 · Score: 0
  
  Don't know which country you live in, but in my country house walls (even internal ones) are made from BRICK. External walls are two bricks thick, internal ones, one brick thick (unless you request the builder to use two). Office buildings tend to be concrete with steal reinforcing.
40. Re:Hmmm... by Anonymous Coward · 2012-05-17 15:38 · Score: 0
  
  Infrared? Not exactly wi-fi. You'd have to be in the same room as the router for this to work. I don't see many practical applications.
  Just think of a classroom in a college, where the students are trying to learn an ERP system, or are doing some system updates of their computers using the college's teaching/learning modules.
41. Re:Hmmm... by evilviper · 2012-05-17 17:51 · Score: 1
  
  " If your walls are made of water or bone, then yes you will need to stay with gigahertz frequencies :P"
  This is an idiotic statement to make. One of the first things you should have learned in science is that damn near EVERYTHING contains water, including rocks... Those wooden walls are holding quite a significant amout of water. That AIR you're breathing has substantial water in it (see humidity). And not to mention things like resonant frequencies of oxygen mollecules...
  With all this stuff absorbing radio energy, you CAN still use these frequencies, but you should be well aware that you need to crank up the power a hell of a lot to compensate for it. Not only does that become impractical, but DANGEROUS, as your WiFi starts functioning like your microwave oven...
  
  --
  Slashdot gets worse every day... Pipedot: News for nerds, without the corporate slant
Also cuts heating costs by Orga · 2012-05-16 07:20 · Score: 2

as the water molecules contained in the upper layers of your skin move in reaction to these waves!
1. Re:Also cuts heating costs by gewalker · 2012-05-16 07:27 · Score: 1
  
  It will be worth it if you can reheat your burrito without having to walk all the way to the kitchen.
2. Re:Also cuts heating costs by Anonymous Coward · 2012-05-16 07:47 · Score: 0
  
  This is why God gave you armpits. They are not just for making entertaining noises.
3. Re:Also cuts heating costs by Anonymous Coward · 2012-05-16 08:03 · Score: 0
  
  You do know that standard wi-fi is the same 2.4 GHz as a microwave oven right?
4. Re:Also cuts heating costs by EdIII · 2012-05-16 08:32 · Score: 1
  
  Yeah. I am very well aware of that. Every time my roommate used to heat up a hot pocket the latency fucking sucked when trying to pwn somebody in Halo :)
I have an ignorant question... by MobileTatsu-NJG · 2012-05-16 07:21 · Score: 4, Interesting

I've heard before that the higher the range of frequency, the harder it is for signals to penetrate things like walls. If we keep advancing along these lines, could this potentially ease our troubles with wifi-over-saturation because we won't be picking up our neighbors' signals?

--

"I like to lick butts!" by MobileTatsu-NJG (#32700246) (Score:5, Informative)
1. Re:I have an ignorant question... by Githaron · 2012-05-16 07:28 · Score: 1
  
  I've heard before that the higher the range of frequency, the harder it is for signals to penetrate things like walls. If we keep advancing along these lines, could this potentially ease our troubles with wifi-over-saturation because we won't be picking up our neighbors' signals?
  I already have trouble get wi-fi through the whole house without multiple APs. You must be living in an apartment or something.
2. Re:I have an ignorant question... by Anonymous Coward · 2012-05-16 07:33 · Score: 0
  
  Terahertz radiation can be stopped quite easily, in a non-ionizing fashion. Hence its proposed use for airport body scanning, as it will only penetrate a few millimeters before being scattered/stopped/absorbed.
  I think it will be difficult to commoditize (word?) t-rays as highly as microwaves are for wifi, etc. due to the attenuation characteristics you are identifying.
3. Re:I have an ignorant question... by wfolta · 2012-05-16 07:37 · Score: 1
  
  The BBC article says, "Terahertz wi-fi would probably only work over ranges of about 10m, but could in theory support data rates up to 100Gb/s - close to 15 times higher than the next-generation 802.11ac wi-fi standard that is under development." So the distance would pretty much limit wi-fi saturation whether its ability to penetrate materials did or not.
4. Re:I have an ignorant question... by MobileTatsu-NJG · 2012-05-16 07:38 · Score: 1
  
  Yes, you're exactly right. It happens at my office, too. We have so many hotspots nearby that I have gotten a stability boost by telling it not to auto-change channels.
  Any suggestions on how I might be doing it wrong would be appreciated. This is not my area of expertise.
  
  --
  
  "I like to lick butts!" by MobileTatsu-NJG (#32700246) (Score:5, Informative)
5. Re:I have an ignorant question... by AngryDeuce · 2012-05-16 08:58 · Score: 1
  
  Yes, you're exactly right. It happens at my office, too. We have so many hotspots nearby that I have gotten a stability boost by telling it not to auto-change channels.
  Same here. At any given moment there are literally 35+ wireless networks within range of my wireless devices, so many that the automatic channel-changing was degrading performance because 2/3 of the routers in the building chase each other across every channel all day long. I've actually fired up my wifi sniffing ap on my phone to show people out of pure amusement; watching it in real time is like watching some sort of competitive sport. It's not even just residential signals, either...there is a strip mall right behind my complex so I pick up half of their networks, as well.
  In the end all I could do is hard-line everything in the apartment, despite how much of a pain in the ass it is to do that in an apartment where you can't drill holes in the walls. Everything that can't be hard-lined has to run via 3/4G, otherwise you're surfing at dial-up speeds.
  There really needs to be some sort of standard method of channel negotiation the router manufacturers can come up with to prevent that kind of crap. I honestly don't know what else they're going to do, short of moving to entirely new bands constantly, but even doing that is only a temporary solution, as the 5 GHz band is just as cluttered as the 2.4 GHz band in this building. There is 100 units within a few hundred feet of each other here...
6. Re:I have an ignorant question... by tlhIngan · 2012-05-16 09:08 · Score: 1
  
  I've heard before that the higher the range of frequency, the harder it is for signals to penetrate things like walls. If we keep advancing along these lines, could this potentially ease our troubles with wifi-over-saturation because we won't be picking up our neighbors' signals?
  Well, 300GHz+ is considered "light" rather than "radio", so it won't penetrate far through the walls. In fact, it may be a bit inconvenient since the only signal is coming through the open door unless you put in a repeater in the same room.
  But yeah, if you switch to 5GHz, it's a lot more open but you'll find range is quite a bit shorter. I'm fairly certain the higher frequencies still are pretty much just-a-bit-more-than-a-room penetration.
7. Re:I have an ignorant question... by jandrese · 2012-05-16 09:12 · Score: 2
  
  Well, it's not exactly legal, but you could tell all of your wireless gear that you are Japanese and switch over to channel 14. You'll be stepping on radiolocation beacons, but those shouldn't be around in the middle of a city anyway.
  
  --
  
  I read the internet for the articles.
8. Re:I have an ignorant question... by MobileTatsu-NJG · 2012-05-16 09:36 · Score: 1
  
  Would those radio location beacons be the sort of thing that airports would find useful?
  
  --
  
  "I like to lick butts!" by MobileTatsu-NJG (#32700246) (Score:5, Informative)
9. Re:I have an ignorant question... by Anonymous Coward · 2012-05-16 18:04 · Score: 0
  
  nah. the useful ones are HF.
10. Re:I have an ignorant question... by jandrese · 2012-05-18 09:01 · Score: 1
  
  No, airport beacons operate on different frequencies, as do maritime ones. I've not been able to find any actual radiolocation devices using that band. There is a patent application for one, but I can't find any examples of one that has been built. The 2.45Ghz band is not a good one for radiolocation anyway, since it is absorbed strongly by water, meaning it will be less effective in storm conditions--which is when you need radiolocation services the most.
  
  --
  
  I read the internet for the articles.
11. Re:I have an ignorant question... by MobileTatsu-NJG · 2012-05-18 09:17 · Score: 1
  
  Ah, okay.
  Thanks for clarifying. I live a close to an airport so I was just being a lil paranoid.
  Have a good weekend!
  
  --
  
  "I like to lick butts!" by MobileTatsu-NJG (#32700246) (Score:5, Informative)
How much is that by Intrepid+imaginaut · 2012-05-16 07:22 · Score: 1

How much is that in median tentacle pr0n movie units per second?
1. Re:How much is that by Anonymous Coward · 2012-05-16 07:32 · Score: 0
  
  Depends on the frame rate of course, but I'd calculate it to about 69. Assuming standard frame rates, stereo sound and 20 minute movie durations.
2. Re:How much is that by NEDHead · 2012-05-16 07:47 · Score: 1
  
  Ah, 20 minute duration. Those were the days...
hehehe, tit by Anonymous Coward · 2012-05-16 07:30 · Score: 1

Tokyo Institute of Technology? hahaha, TIT.
Yes by LanMan04 · 2012-05-16 07:31 · Score: 1

Yes, you're right. After all, visible-light is pretty damn high-frequency and it sucks at penetrating walls.
Visible light: 400 to 700 nm
Far Infrared: 15,000 nm to 1,000,000 nm
Regular wifi: 125,000,000 nm
I have no idea at what wavelength drywall and other modern building materials start seriously attenuating a signal (as in "only good for line-of-sight" attenuating). Anyone?

--
With the first link, the chain is forged.
1. Re:Yes by NEDHead · 2012-05-16 07:46 · Score: 2
  
  As I recall, drywall never attenuated the noise in the next dormroom very well. This was a pre PC experience however.
2. Re:Yes by Anonymous Coward · 2012-05-16 07:51 · Score: 1
  
  Those were low frequency signals. Penetration was the whole point.
we don't need windows where we're going.... by Anonymous Coward · 2012-05-16 07:33 · Score: 2, Funny

That doesn't really matter because you are stupid.
No you are... He/She is right. Turns out IR doesn't go through walls too well.
Works just fine if you up the transmitter power enough.
What are you, some sort of girly man?
1. Re:we don't need windows where we're going.... by Nadaka · 2012-05-16 08:06 · Score: 1
  
  yea, emit enough IR and you can make those pesky walls burn away.
2. Re:we don't need windows where we're going.... by EdIII · 2012-05-16 08:21 · Score: 1
  
  yea, emit enough IR and you can make those pesky Balls burn away.
  I think that is what we are concerned with most....
Riddle by Anonymous Coward · 2012-05-16 07:34 · Score: 1

Q: What do you call electromagnetic waves at Terahertz frequencies on the other side of a wall?
A: Utterly useless.
Just answered my own question by LanMan04 · 2012-05-16 07:34 · Score: 5, Informative

"Terahertz radiation is non-ionizing submillimeter microwave radiation and shares with microwaves the capability to penetrate a wide variety of non-conducting materials. Terahertz radiation can pass through clothing, paper, cardboard, wood, masonry, plastic and ceramics. It can also penetrate fog and clouds, but cannot penetrate metal or water."
http://en.wikipedia.org/wiki/Terahertz

--
With the first link, the chain is forged.
1. Re:Just answered my own question by cdibbs · 2012-05-16 09:00 · Score: 1
  
  So it won't work very well in humid environments. "Sorry, boss, the wife took a long shower."
2. Re:Just answered my own question by swillden · 2012-05-16 09:22 · Score: 1
  
  It can also penetrate fog and clouds
  So it won't work very well in humid environments.
  Fog and cloud are humid environments.
  
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3. Re:Just answered my own question by jd · 2012-05-16 09:47 · Score: 1
  
  So it'll be useless in England or the US' Pacific Northwest.
  Although it can penetrate a wide range of materials, that doesn't mean there's zero reflection. I'm much less interested in this for Wifi and much MORE interested in it for building a GPR, since it is essentially illegal in the US for garage developers to experiment with GPR technology (you can't even get the license to operate one unless you've a provable corporate need or are military). If these frequencies aren't regulated, FCC rules prohibiting any kind of private GPR research don't apply.
  
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4. Re:Just answered my own question by Nethead · 2012-05-16 10:17 · Score: 1
  
  Ground Penetrating Radar research? How much power do you need? There are nice chunks of UHF, SHF and EHF frequencies available to hams. (http://www.arrl.org/frequency-allocations) Are there other US TLAs that keep you from pointing you ham antenna at the ground? (CQ CQ CQ DX!) You would just have to incorporate your call sign in your modulation every 10 minutes.
  And regarding PNW rain, Terabeam Free Space Optics started in Seattle. I had rackspace in the same colo that they started in (Westin Building.)
  
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  -- I have a private email server in my basement.
5. Re:Just answered my own question by jd · 2012-05-16 11:36 · Score: 1
  
  GPR is very low power, as transmissions go. The higher-power high-end 2.4 GHz and 5 GHz radars out there can manage 10 feet through soil but typical sets will manage about half that. Although people will talk about GPR not working well when there's water around, I've no particular interest in trudging through muddy fields in heavy rain. That kind of stuff only really affects corporate and military users, where there's very specific time constraints involved.
  My interest is in building GPR systems that are specifically for archaeology, where your time window is measured in centuries not hours, so waiting until the ground is dry is a non-issue. However, excavations are slow and expensive, so you've got to pick where you look with a lot of care.
  The crucial difference is that in archaeological surveys, you want a LOT of data. You care about shadows, reflections at weird angles, the refractive indexes of different materials and other details that "regular" GPS users consider anomalies. Because the regular users don't want that data, it's generally eliminated from the data set. Which is fine for what they're doing. If you know there are N pipes and one has a fracture, you want to see N lines with one line being different (doesn't matter how) from the rest. That's your typical corporate and local authority use case. The military want to spot mines, IEDs and UXBs, but they don't need to know if the objects surrounding it are remnants of a Greek statue or just randomly-shaped lumps of rock.
  High frequencies = high resolution, but limited depth; Low frequencies = low resolution, but greater depth. In theory, you'd want a mix to learn everything but nobody actually does that.
  UHF, SHF and EHF should all be fine. The government position is that civilians don't need GPR, that it's a military technology, and to hell with scientists who say otherwise. However, as far as I know only the FCC actually restricts the technology. Pointing a ham antenna at the ground is an interesting idea, might actually work very well. Incorporating the call sign into the signal would be easy.
  
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6. Re:Just answered my own question by Nethead · 2012-05-16 15:15 · Score: 1
  
  The basic Technician license lets you have full privileged above 50MHz. It's about as hard as getting a food worker permit. The FCC rules for ham are designed for experimentation. They let people use 1.5KW (input, not ERP) to feed gain antennas at VHF/UHF to bounce signals off the moon. I can't recall anything that wouldn't let you pump a few dozen watts into the ground.
  Email me if you need help getting licensed.
  Also note that ham and wifi share some bandwidth, but a ham can run much more power. Some people mod OTS wifi devices to use ham only frequencies for long haul microwave backbones. You ID by putting you callsign in as the MAC.
  
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  -- I have a private email server in my basement.
7. Re:Just answered my own question by cdibbs · 2012-05-18 13:55 · Score: 1
  
  Hah. Missed that, somehow. Nevertheless... depending on the application, I probably wouldn't trust a technology that can penetrate water vapor, but not water, until I learned a bit more about the specifics.
Re:Fry Me a Couple by Moheeheeko · 2012-05-16 07:37 · Score: 1

Because tested once in a lab = on store shelves without further testing next week, right?
The downside is... by Cyko_01 · 2012-05-16 07:40 · Score: 1

It requires line of sight and only has a range of 1-3 meters without significant power boosting. In other words.....you are better off just running wires
1. Re:The downside is... by jd · 2012-05-16 10:11 · Score: 1
  
  Since the lower frequencies can pass through rock, it's safe to say line of sight isn't necessary. However, the limited range is a problem and as 100 Gb/s is already achievable by Ethernet (300 Gb/s for Infiniband), it's not clear what the benefit is of adopting a technology that will max out (in the future) at the speeds you can get now, when most of the benefit of wireless really won't apply.
  
  --
  It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
2. Re:The downside is... by JSBiff · 2012-05-16 14:43 · Score: 1
  
  Seems like it'd be useful for something like a "Wireless HDMI" standard, to allow your computer, phone, etc to transmit HD video to your TV or projector.
Applications by Beryllium+Sphere(tm) · 2012-05-16 07:41 · Score: 1

Media center interconnects. Large rooms, e.g. event centers.
At last! by _0x783czar · 2012-05-16 07:41 · Score: 1

*reconfigures pirate radio station to broadcast in FIR frequencies*

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~theCzar
1. Re:At last! by Anonymous Coward · 2012-05-16 08:10 · Score: 0
  
  *reconfigures pirate radio station to broadcast in FIR frequencies*
  Yeah, I could never get those IIR frequencies to remain stable.
Naked scanner from your terahertz wifi card? by madbavarian · 2012-05-16 07:45 · Score: 2

If terahertz wifi cards become generally available, how long before we see articles about people repurposing the hardware to do terahertz reflective imagery like the security guys already do for looking through walls to spot people in a room or look through cloths to see "weapons"?
http://www.dailymail.co.uk/sciencetech/article-2131932/The-REAL-X-Ray-spex--new-terahertz-scanner-lets-mobile-phones-walls.html
1. Re:Naked scanner from your terahertz wifi card? by Anonymous Coward · 2012-05-16 08:49 · Score: 0
  
  If terahertz wifi cards become generally available, how long before we see articles about people repurposing the hardware to do terahertz reflective imagery like the security guys already do for looking through walls to spot people in a room or look through cloths to see "weapons"?
  Never. People already use microwave frequencies for imaging. It's called radar. Wifi cards use microwaves and are dirt cheap. Yet, there are no wifi card based radars, because what's in wifi cards and what's in a microwave radar is drastically different. Your TV remote control uses light and so does a camera, but would you expect to use a remote control to take a picture in infrared? Transmitting data and imaging are very very different applications.
Re:Fry Me a Couple by thedonger · 2012-05-16 07:51 · Score: 1

Because tested once in a lab = on store shelves without further testing next week, right?
No, but tested for five years does not equal 20 years of exposure. Those crazy unknown unknowns...

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Re:Fry Me a Couple by compro01 · 2012-05-16 07:52 · Score: 3, Funny

Quickly! Shut off your monitor. It is bombarding you with radiation in the hundreds of terahertz!

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Try Concrete by Bananatree3 · 2012-05-16 07:56 · Score: 1

Concrete is dense by every definition.
1. Re:Try Concrete by Eponymous+Hero · 2012-05-16 08:03 · Score: 1
  
  http://www.concretex-ray.com.au/wall-x-ray
  
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2. Re:Try Concrete by Bananatree3 · 2012-05-16 08:07 · Score: 2
  
  U win!
3. Re:Try Concrete by h4rr4r · 2012-05-16 08:27 · Score: 1
  
  Very few walls are concrete. Even in office buildings only the exterior walls are likely to be concrete.
4. Re:Try Concrete by AngryDeuce · 2012-05-16 08:43 · Score: 1
  
  How many houses have you lived in that were built out of concrete, Vault Dweller?
5. Re:Try Concrete by Grishnakh · 2012-05-16 08:57 · Score: 1
  
  Here in Arizona, most of the houses are built out of concrete. It's called "stucco": it's a thin layer of concrete sprayed on top of some substrate (possibly drywall; these houses are dirt-cheap). Obviously, if you're only interested in networking inside your building that's not a problem, but if you're trying to communicate outside your house the walls will be a problem.
  In other parts of the country, bricks are still pretty popular for exterior walls, even if they're just a facade.
6. Re:Try Concrete by Taty'sEyes · 2012-05-16 08:59 · Score: 2
  
  Remember his POV, basement walls tend to be concrete.
  
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7. Re:Try Concrete by rev0lt · 2012-05-16 09:17 · Score: 2
  
  I know some houses that have concrete walls. And where I live, granite houses are pretty common (and they have some internal master walls made of granite). My house is made of bricks and a layer of concrete, and lots of apartments, office buildings and schools are built the same way.
8. Re:Try Concrete by inglorion_on_the_net · 2012-05-16 09:17 · Score: 1
  
  This is awesome! The claim earlier in the thread that far infrared penetrates similarly to x-ray means that far infrared could be used instead of x-ray for this purpose.
  
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  Please correct me if I got my facts wrong.
9. Re:Try Concrete by Anonymous Coward · 2012-05-16 12:57 · Score: 1
  
  In Brazil, the regular wall of homes and offices are made of bricks. Much denser than regular US walls.
10. Re:Try Concrete by Ghaoth · 2012-05-16 14:01 · Score: 1
  
  you lot obviously don't live in cyclone (hurricanes) prone areas.
  
  --
  Nos Morituri te salutamus
11. Re:Try Concrete by 0111+1110 · 2012-05-16 15:08 · Score: 1
  
  Nice Fallout reference, but a very large number of houses in warm areas of the planet are built out of either poured concrete forms or concrete block. It's unusual in the US for residential construction which is nearly always stick frame, but the rest of the world actually builds that way quite a bit.
  In fact pretty much every house I have lived in outside of the US used concrete construction at least for the exterior walls. The interior walls are often concrete as well.
  
  --
  Quite an experience to live in fear, isn't it? That's what it is to be a slave.
A function of frequency by Grindalf · 2012-05-16 07:57 · Score: 0

Since transmission speed is a function of frequency, then I suspect that a much higher bandwith is possible.

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Major advance, stupid article by Animats · 2012-05-16 08:00 · Score: 4, Interesting

The real news here is that terahertz electronics is getting small, and potentially cheap. That has many uses. Most of them, though, do not involve data transmission. Terahertz radar will be useful for medical imaging, security, and driverless cars. There will probably be manufacturing applications, like quick 3D profiles of objects for inspection and measurement.
Point to point terahertz data transmission probably isn't that useful. Point to point laser links have never been very useful. At light and near-light frequencies, rain, snow, and fog will block the beam. If you want one, outdoor laser links are commercially available.
Re:Fry Me a Couple by lgw · 2012-05-16 08:07 · Score: 1

Sorry, I'm not going to be scared of any new technology without some scientific basis for how the new thing could possibly cause me harm. I'm damn conservative for a /.er, and even I get that right.
If we can't even chase the Luddites off /., what good is this place?

--
Socialism: a lie told by totalitarians and believed by fools.
Too fragile to be useful by Anonymous Coward · 2012-05-16 08:31 · Score: 0

A mosquito fart would interfere with the signal.
I'm a Nazi by Anonymous Coward · 2012-05-16 08:32 · Score: 0

and it is called "line of sight".
BAAAD Tactic by Anonymous Coward · 2012-05-16 08:35 · Score: 0

Ms Eve(sdropper) will point a powerful telescope at your window and get a sufficient signal.
Re:Fry Me a Couple by Dishevel · 2012-05-16 08:39 · Score: 1

Right.
We should test all hair conditioners, life saving drugs, cell phones and computers. Anything that has chemicals or might emit scary radiation for 20 years before even thinking of releasing it.
Can I please go somewhere sane?

--
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Every Microwave Oven Is a Jammer by Anonymous Coward · 2012-05-16 08:39 · Score: 0

Just short the switch protecting the 600W tube from being operated with the door open. Then point it out of the window towards your finance district. That will basically take out the next few square miles of Wifi.
Researchers at the TIT develop new WiTS by bura · 2012-05-16 08:45 · Score: 0

Whats wrong with the editors, wouldnt this article have better interest if it had a better title? Researchers at the TIT (Tokyo Institute of Technology) have developed a new WiTS (wireless transmission system)
Re:Fry Me a Couple by AngryDeuce · 2012-05-16 08:45 · Score: 1

And for the love of God stay away from the big ball of radiation we call "the sun"!
There they go! by Anonymous Coward · 2012-05-16 08:46 · Score: 1

There go the rest of the bees!
1. Re:There they go! by Shompol · 2012-05-16 13:32 · Score: 1
  
  I think some researchers recently came to a conclusion that bees get wiped out due to widespread use of pesticides and insecticides. We might, of course, plop some bee-sized tinfoil hats and see how that works out :)
Re:Fry Me a Couple by Culture20 · 2012-05-16 08:49 · Score: 1

Sorry, I'm not going to be scared of any new technology without some scientific basis for how the new thing could possibly cause me harm. I'm damn conservative for a /.er, and even I get that right.
It uses Tera-hertz radiation. That's what the TSA uses for the nudie scanners they use to grope you!

If we can't even chase the Luddites off /., what good is this place?
It's a safe bet that no one on /. is a luddite. It is a website after all.
WAR by Anonymous Coward · 2012-05-16 08:50 · Score: 0

They already use 100THz range frequencies for high-resolution seeker radar. I am not sure as to what the benefits are as compared to simply using an IR Laser, but it might have something to to with A) ability to modulate signal and perform ranging B) better penetration of clouds, fog and countermeasures.
http://www.slideshare.net/aticourses/tactical-missile-design
Re:Fry Me a Couple by lgw · 2012-05-16 09:07 · Score: 1

It's a safe bet that no one on /. is a luddite. It is a website after all.
Do you actually read the comments much? Never have I seen so much backlash against any new idea or technology - it baffles me, TBH.

--
Socialism: a lie told by totalitarians and believed by fools.
Dinner Anyone? by glorybe · 2012-05-16 09:24 · Score: 1

You might be able to cook a turkey at those frequencies.
At some point, does any more speed matter? by Anonymous Coward · 2012-05-16 09:40 · Score: 0

So you can download the entire internet in a minute. Then what? And where are you going to put it?
1. Re:At some point, does any more speed matter? by Per+Wigren · 2012-05-17 05:01 · Score: 1
  
  So you can download the entire internet in a minute. Then what? And where are you going to put it?
  In the cloud, of course.
  
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Re:Fry Me a Couple by Culture20 · 2012-05-16 10:02 · Score: 1

Do you actually read the comments much?
Haven't you heard? Not RTFC is the latest in geek chic!
Re:Fry Me a Couple by jd · 2012-05-16 10:05 · Score: 3, Funny

I am Icarus, and I approve of this message.

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It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
Same room? ;-) by PaulBu · 2012-05-16 10:31 · Score: 1

Why does transmission have to happen in the "room", and not, say, "outside the room", to, say, a satellite 50,000 miles away?
And, why only 3 Gbps??? Check this one out: http://www.irconnect.com/noc/press/pages/news_releases.html?d=118076
Definitely infrared (THz for some definition of THz) carrier, with up to 40 Gbps datarate, able to go to and from a big router in space...
In the interest of full disclosure, I have been working on a small part related to that program in my past, so immediately reacted along the lines of "Wait a minute, what about Northrop LaserComm???"... ;-)
Paul B.
Beam steering by Animats · 2012-05-16 13:18 · Score: 2

I am not sure as to what the benefits are as compared to simply using an IR Laser
Hopefully, electrical beam steering. IR lasers still have to be steered with moving mirrors. On the receive side, you need a big moving mirror, because you need big collecting optics to get any significant range. If phased array techniques can be made to work in that band, scanning devices won't need moving parts. 3D LIDAR scanners are still expensive, clunky devices.
Currently regulated spectrum frequencies? by dgharmon · 2012-05-17 02:29 · Score: 1

"Researchers at the Tokyo Institute of Technology have developed a new wireless transmission system that works above all currently regulated spectrum frequencies. The new system works at the range of 300GHz to 3THz (terahertz), which is the Far Infrared (FIR) frequencies of the infrared spectrum"

Except such frequencies are prone to interference and don't travel far and don't work well when the transmitter and receiver are moving, which means you need lots of base stations.

"Terahertz wi-fi would probably only work within ranges of about 10m "

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