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Record High Frequency Achieved
eldavojohn writes "Researchers at UCLA Henry Samueli School of Engineering and Applied Science managed to push our control of frequencies to another level when they hit a submillimeter 324 gigahertz frequency. As any signal geek out there might tell you, this is a non-trivial task. 'With traditional 90-nanometer CMOS circuit approaches, it is virtually impossible to generate usable submillimeter signals with a frequency higher than about 190 GHz. That's because conventional oscillator circuits are nonlinear systems in which increases in frequency are accompanied by a corresponding loss in gain or efficiency and an increase in noise, making them unsuitable for practical applications.' The article also talks about the surprising applications this new technology may evolve into."
The article also talks about the surprising applications this new technology may evolve into
Like making your dog's head explode.
Think of the bees :p
No folly is more costly than the folly of intolerant idealism. - Winston Churchill
Precision phase coherent control of lasers has become possible in the last ten years- Laser beams at frequencies exceeding 1 PHz (10^15 Hz) have been precisely controlled, phase locked, and tuned to have frequencies that are *exact multiples* of our best microwave frequency standards (e.g, cesium). It works the other way too-- our most precise microwave-frequency signals come from divided-down optical frequency references now! See also: 2005 nobel in physics.
More than 15 years ago, quite a few of the students at the physics lab I was teaching had their oscillating circuits reach 483 terahertz and more pretty easily. For a short amount of time that is.
... how they are able to visualize such high frequencies. How do they know they succeeded?
The more you regulate a company, the worse its products become.
They found frequencies... they didn't even know existed?!
+1 funny
-8 bad movie
-9000 overrated
-- 'The' Lord and Master Bitman On High, Master Of All
Check out http://www.arrl.org/qst/worldabove/dxrecords.html for the Amateur Radio DX records. This was achieved long ago and at higher frequencies. Highest RF frequency used for a confirmed two-way communication was 403 GHz between WA1ZMS/4 (FM07ji) and W4WWQ/4 (FM07ji) on 21-Dec-2004 over a distance of 1.42 kilometers. Achieving a frequency is one thing but being able to use it is another.
This technology is another step along to road to widespread technology exploiting Terahertz radiation, which is the region of the EM-spectrum between IR and microwaves. Near the end of the article, they mention the possibility of creating imaging systems that can, for example, see through clothes. These applications of so-called T-rays have in fact already been demonstrated. For example, the image in this article shows a man concealing a knife, which is easily visible in the T-ray image. (See also some other pictures here.) T-rays reflect strongly off of metals but can penetrate to varying extents through things like clothing and tissue. The military and security applications are obvious. However it would also bring up new kinds of medical imaging, and has been investigated for quality control, too (for example, scanning the inside of foods in assembly lines, etc.). In the previous link I put, there is an example of scanning through a Hershey bar, where you can see the positions of the nuts.
Suffice it to say this is an area of active research that may have many, many applications.
If aliens are calling then they'd probably be using frequencies along those lines. The logic would be that if they found using such frequencies to be technologically challenging to use why would they bother to communicate with an abundance of lesser civilizations when they could potentially benefit from communicating with equal or superior civilizations across the cosmos?
- John
http://www.jabcreations.com/
Red/orange LEDs typically have a lifetime measured in the 10,000+ hour range, when reasonably driven. A $1 blue LED will provide a reliable 600+ THz.
"National Security is the chief cause of national insecurity." - Celine's First Law
My flashlight achieves orders of magnitude higher frequencies in a snap!
People across the nation began shitting themselves for no apparent reason. Victims recall feeling an unusual vibration in their bowels before immediately discharging feces. Some believe an evil genius may have finally discovered the "brown note". For Action 11 news I'm....oh god.....>PPHHBBBBHHTTHHHHH!!!!!
Take that Mythbusters!!!
Sincer "submillimeter" implies a frequency greater than 300GHz, it makes no sense to talk about "usable submillimeter signals with a frequency higher than about 190 GHz".
This post was clearly planted by the U.S. government.
"When the atomic bomb goes off there's devastation...but when the atomic bong goes off there's celebraaaaation!"
What they did sounds like an extension of the technique used in push-push oscillators to "double" the oscillation frequency.
The basic principle behind a push-push oscillator is that two out-of-phase signals of fundamental frequency f_o are combined such that the fundamental signal and the odd harmonics cancel, while the second harmonic at 2*f_o add constructively. In the case of a push-push oscillator, you only need two signals 180 degrees out of phase. This could be generated with a differential VCO.
Using a push-push oscillator is a well known technique for increasing the frequency of oscillation of a VCO beyond the fMAX of a transistors at a given process node.
The only disadvantage with push-push oscillators is that you end up losing a lot of power as the second harmonics's power will always be much smaller than the power in the fundamental frequency of the VCO.
So will we now start seeing tinfoil underwear to go with the hats?
... as it will finally allow a PC processor to run at the speeds necessary to have fluent Vista GUI ... now if someone would invent the 16TB ram chip, so that the also necessary 64TB of main memory could be added to said machine ...
I can create an even higher frequency for a fraction of the cost.
(Turns on flashlight)
I can even send information.
(Blinks flashlight)
I admit the data capactity needs work, though.