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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
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.
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.
It isn't if you attach it to sharks. Then, instead, it's deadly.
Do NOT click the above link!!!!!!
The cake is a lie.
We should be able to implement a filter that stops these kinds of posts within a few years.
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.