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Terahertz Wireless Chip Will Bring 30Gbps Networks
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."
Build your own fully body scanner.
What can I do with 30 GiB/s? I'm trying to figure that out, give me some ideas.
To offset political mods, replace Flamebait with Insightful.
ISPs will still throttle your ass to 55 Mbps
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.
What do I know, I'm just an idiot, right?
"...it's more like a laser than a signal..."
A laser is a signal
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.
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?
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
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.
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.
Good people go to bed earlier.
...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.
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
Do NOT click the above link!!!!!!
The cake is a lie.
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"?
Having to work for a living is the root of all evil.
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.
I read the internet for the articles.
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.
The determined Real Programmer can write Fortran programs in any language.
Three ad-heavy blogs deep, the best I'm able to find is a brief note in Electronics (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 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.
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, 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.
I can see it now. XXX websites dedicated to upskirt full body scan pr0n.
The world's burning. Moped Jesus spotted on I50. Details at 11.
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?
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) 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.
So basically wireless will eventually be like fibre ?
New things are always on the horizon
Seems to me you could quite easily use them to connect houses in an urban setting. Since they're cheap you could use one device for every home and since they're highly directional you could turn them off and on depending upon whether the homeowner wants to be connected (or has paid the bill). Put 15 or 20 in a central location and one at each house. This eliminates all the complexities of getting individual fiber to the houses, too.
No one ever had to evacuate a city because the solar panels broke!
As an IT nerd, I've used my fair share of 802.11g and 802.11n networks.
802.11g I have never, ever seen more than 3.0MBytes/s sustained transfer rate about 24mbits.
802.11n I've delt with mostly 300mbit equipment, the highest sustained and consistent speed I've seen is 10MBytes/s across a large transfer, the average I would say is 5 or 6 but I have seen a sustained 10 multiple times. NEVER faster, ever! That's 80mbits per second.
On a 100mbit network, I've never seen a sustained speed of over 10 to 11MBytes/s, not the 12.5 it's theoretically capable of - so as nerds we all know about overhead. Wireless obviously is higher than wired.
That being said, it seems to me that the speed quotes are often a load of cobblers. 30gbit/s I'd be surprised if in the real world you saw more than 2 or 300MB/ytes per second sustained (if the disk is even capable)!