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DARPA Creates 0.85 THz Solid State Receiver
hypnosec writes "DARPA, under its THz Electronics program, has designed a solid state receiver capable of THz (terahertz) frequencies thus inching towards the possibilities of transistor-based electronics that will operate at THz frequencies. The newly designed solid state receiver demonstrates a gain at 0.85 THz. This particular milestone is a stepping stone for the next target of 1.03 THz. Because of this achievement a host of DoD electronics capabilities can now be realized. One such application where this can be of use is for a sensor that will operate through clouds under a DARPA program dubbed VISAR."
Not just for airports any more. With technology like this, they can start minaturising the tech so every cop doing a stop-and-search can inspect the suspect. For, ah, weapons. Of course.
... or are they going to try to make a CPU/GPU core at this speed?
now we need to go OSS in diesel cars
It's "gain at 0.85 THz", not "of".
Article summary is incorrect.
Sorry, EE major and I get annoyed reading this kind of thing...
I want to make an oven with these things! Just think, the speed of a microwave with th heating properties of a regular oven!
I'm and so there! The T-Wave oven!
Since microwaves use GIGAherts frequency and have MILLImeter wavelengths, why do they call them MICROwaves? :/
Here is what they want this for:
This revolutionary advance would give U.S. warfighters an advantage in an especially challenging portion of the RF spectrum
As per usual, it's all for war, it's all that government is interested in.
You can't handle the truth.
I can do morse code at 1Hz, also known as 0.000000000001THz. Look! THz frequencies. 0.85THz is fast, but just because you used THz as the unit of measurement doesn't mean you have accomplished THz speeds.
Another terrible article summary.
In 2010, a solid-state device at 0.67THz was achieved. In 2012, that effort is up to 0.85 THz. Progress is slow, but continuing.
Diode-type CMOS imagers for terahertz radiation have been built. Those convert terahertz radiation into DC, which can then be amplified by standard techniques. But diodes don't have gain. That's why the original article emphasizes that this new device has gain.
There are terahertz lasers, waveguides, antennas, and other components that work up there. The situation is much like radar during WWII; there were a few components that could do specific things at radar frequencies (then 60MHz to 1.2GHz), but general electronics wasn't there yet. Most of the electronics in radars of that period ran at far lower speeds. They still worked.
Probably unity gain at 0.85 THz.
Let's not make it bigger than it really is !! My ethernet is 10 GHz !! And it's punky PC stuff !!
Wouldn't a 1.03 Thz EM wave, by definition, been what we call Infrared light? And if so, why the race for this when we already have tons of cheap options for generating and detecting infrared light? I realize I'm the daft one here and not the scientists, but could someone explain what the difference is between their (eventual) 1.03 Thz solid state "receiver" and say an off the shelf $0.20 IR detector that's been available for decades?
It may have demonstrated 0.1dB of gain at 850GHz (seriously, let's not label it THz unless it actually makes THz), but unless it is linear, it is pretty useless for digital communications.
Does anyone here know of the term "Terahertz radiation"? Why are people saying things like "my eye is a Terahertz receiever" or "0.85 Terahertz isn't really Terahertz"?
http://en.wikipedia.org/wiki/Terahertz_radiation
You know that this is at least 30 years old...???
The summary and linked press releases are light on details so here is what I gleaned from the photograph of the chip based on some experience in the area of microwave/mm-wave device and circuit work. There will probably be much more technical information in upcoming papers in the research literature.
Based on the photo of the chip on the linked DARPA page this is not a receiver, but a low-noise amplifier (LNA) which would be used as the front-end for an imaging sensor or communications/radar receiver. It would be straightforward to turn this into an imaging detector at this point by adding a detector after the LNA though I don't think this has one. For a synthetic aperture radar more circuits will be required, especially a mixer to downconvert the frequency.
The slashdot summary misquotes the article saying that the circuit has "gain of 0.85 THz" but should say "gain at 0.85 THz". The LNA appears to have 10 amplifications stages which is very large for a LNA, which suggests that the gain per stage is still quite low at 0.85THz. This is to be expected as the best per-transistor gain cutoff frequencies are not too far 1THz that I'm aware of. The circuit also appears to be built in coplanar waveguide (a metallized signal strip in the middle surrounded by two ground strips) which is easy to fabricate and good for a research environment but it has a higher loss than microstrip (a signal line above a ground plane).
Anyway that's my 2 cents.
Just like me, I have mega-bucks. 0.000002 million bucks in my pocket right now! If I put it in the bank, with interest it will have gain.
Problems that I've post9s. Due to the the party in street But with Netcraft
So this thing can receive signals at (just less than) a TeraHz... But is somebody transmitting on that frequency?
Obviously the higher the frequency the more bandwidth is available but what about the characteristics of the atmosphere ? Is this for long distance communication? wouldn't clouds etc screw it up?
When a government agency funds something that works, the headline is always, "NASA builds this..." or "DARPA builds that..."
But when a government agency funds something that doesn't work, the headline instead is, "Lockheed mess up this..." or "Boeing messed up that..."
Did DARPA "create" this as the headline says, or did they just fund somebody else to do the research, design and implementation?
http://www.laserfocusworld.com/articles/2012/07/northrop-grumman-demos-850-ghz-integrated-receiver-circuit-aiming-at-terahertz-photonics.html
I hope that after I die the one word people use to describe me is "resurrected."
Geordi La Forge's VISOR allowed him to see between 1 hz and 100,000 THz. Isn't it kinda interesting that they used a name so similar?
When I was doing war toys, not all that long ago, (ok, I guess it was. Where did the time go?) 40 Ghz was considered really, really high.
Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
"VISAR seeks to develop and demonstrate a targeting sensor which operates through clouds as effectively as today’s infrared (IR) sensors operate in clear weather. This revolutionary advance would give U.S. warfighters an advantage in an especially challenging portion of the RF spectrum.”
The wars of the future will not be fought on the battlefield or at sea. They will be fought in space, or possibly on top of terahertz waves.
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it goes to 11.
Yes, I joke there. I do find it fascinating how stuff keeps getting pushed to the limits, and then we say "bah, we can do better!"
Vote monkeys into Congress. They are cheaper and more trustworthy.
The most important question: how will we divide the THz bands into Extra, Advanced, General, Technician, and Novice?