Engineers Discover How To Make Antennas For Wireless Communication 100x Smaller Than Their Current Size (sciencemag.org) 129
Engineers have figured out how to make antennas for wireless communication 100 times smaller than their current size, an advance that could lead to tiny brain implants, micro-medical devices, or phones you can wear on your finger. Science Magazine reports: The new mini-antennas play off the difference between electromagnetic (EM) waves, such as light and radio waves, and acoustic waves, such as sound and inaudible vibrations. EM waves are fluctuations in an electromagnetic field, and they travel at light speed -- an astounding 300,000,000 meters per second. Acoustic waves are the jiggling of matter, and they travel at the much slower speed of sound -- in a solid, typically a few thousand meters per second. So, at any given frequency, an EM wave has a much longer wavelength than an acoustic wave. Antennas receive information by resonating with EM waves, which they convert into electrical voltage. For such resonance to occur, a traditional antenna's length must roughly match the wavelength of the EM wave it receives, meaning that the antenna must be relatively big. However, like a guitar string, an antenna can also resonate with acoustic waves. The new antennas take advantage of this fact. They will pick up EM waves of a given frequency if its size matches the wavelength of the much shorter acoustic waves of the same frequency. That means that that for any given signal frequency, the antennas can be much smaller. The trick is, of course, to quickly turn the incoming EM waves into acoustic waves.
The team created two kinds of acoustic antennas. One has a circular membrane, which works for frequencies in the gigahertz range, including those for WiFi. The other has a rectangular membrane, suitable for megahertz frequencies used for TV and radio. Each is less than a millimeter across, and both can be manufactured together on a single chip. When researchers tested one of the antennas in a specially insulated room, they found that compared to a conventional ring antenna of the same size, it sent and received 2.5 gigahertz signals about 100,000 times more efficiently, they report in Nature Communications.
The team created two kinds of acoustic antennas. One has a circular membrane, which works for frequencies in the gigahertz range, including those for WiFi. The other has a rectangular membrane, suitable for megahertz frequencies used for TV and radio. Each is less than a millimeter across, and both can be manufactured together on a single chip. When researchers tested one of the antennas in a specially insulated room, they found that compared to a conventional ring antenna of the same size, it sent and received 2.5 gigahertz signals about 100,000 times more efficiently, they report in Nature Communications.
3-5 Years (Score:1)
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Antennas in my fillings are receiving Ronald Reagan speeches about host files.
APPS!
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There was an urban legend that a man with a drill bit or titanium implant was able to hear BBC Radio 1 whenever he drove near a large national radio transmitter.
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"There was an urban legend that a man with a drill bit or titanium implant was able to hear BBC Radio 1 whenever he drove near a large national radio transmitter."
Lots of people hear voices in their heads, no antennas or transmitters needed.
We call them, mmmh, what's the word ... Mr. President.
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There are many words for them my son, "progressives, liberals, antifa, blm, snowflake". You'll know them by their violent behavior and inability to co-exist with any who do not share the voices in their heads.
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There are many words for them my son, "progressives, liberals, antifa, blm, snowflake". You'll know them by their violent behavior and inability to co-exist with any who do not share the voices in their heads.
Remember "Taystee".
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Get near a large radio transmitter, and any chunk of metal will receive the signal to some extent. If it is AM, then demodulation practically happens automatically - so if any of the signal gets turned into audio - almost no matter how inefficient - you could get something hearable. They transmit kw/MW, but mW is enough for hearing.
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There was an urban legend that a man with a drill bit or titanium implant was able to hear BBC Radio 1 whenever he drove near a large national radio transmitter.
Lucille Ball was convinced that she picked up radio transmissions in her teeth. Music first and Morse code later IIRC.
Re:3-5 Years (Score:4, Funny)
Actually, that does a lotta splainin.
Re: 3-5 Years (Score:3, Informative)
No, they did it in order to measure the efficiency precisely, which requires shielding from both outside interference and internal reflections.
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Brain implants is an unlikely application, but perhaps you will be able to listen to radio on your phone without having to use the headphone cable as antenna.
At least one of the links provided plenty of information without being behind a paywall. Unfortunately I can't be bothered to read it.
But since we all are here to complain about problems that we don't know if they even exists I'm going to say that to problem with this new technology might be that it is too narrowband to be usable.
A lot of radio applica
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"Brain implants is an unlikely application,"
Why not, "Oath of Fealty" anyone? I would get one.
Re:3-5 Years (Score:5, Interesting)
Well, for what it's worth, TFA says:
"In this work, the demonstrated ME antennas span a wide range of frequencies from 60MHz to 2.5GHz, which are realized by a geometric design of resonating plates that exhibit different mode of vibrations"
and
"It is notable that ME NPR antenna arrays with multiple frequency bands from MHz to GHz can be integrated in one wafer by designing the ME NPR with different lateral dimensions (or W), since the fr,NPR is inversely proportional to W27. This allows the broadband ME NPR antenna arrays on the same wafer, which compensates for the narrowband operation frequencies of ME antennas."
Re:Different use for antennas (Score:4, Funny)
Over-The-Air television
Wait! What? Is that legal? I'm going to ask my gender transition counselor about that. I don't believe people really broadcast valuable content around... no way bro.
Re:Different use for antennas (Score:5, Funny)
No more ... having a lightening attractor on the roof.
Not only does a white roof look better, it actively prevents global warming, as it reflects more sunlight back into space. If anything we need to lighten more of them!
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Unfortunately, the most common "lightener" is bird poop. We actually need *bigger* antennas if we're going to cover the entire roof.
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You could use it to charge your recycled laptop batteries that power the house...
https://hardware.slashdot.org/... [slashdot.org]
Chu limit (Score:3)
Chu's pragmatic boundary (Score:5, Informative)
Chu's limit appears to have been somewhat pragmatic in assuming that certain kinds of electrical circuits could not be feasibly realized.
Chu's Limit—a limit no more [phys.org] — 23 February 2017
The part I understand: built and measured.
Re:Chu's pragmatic boundary (Score:5, Interesting)
The Chu Limit applies to passive antennas. The antenna described in your citation isn't passive; that "non-Foster" term means it's an active antenna. The phys.org title implying some sort of breakthrough physics is click bait.
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The Chu Limit applies to passive antennas. The antenna described in your citation isn't passive; that "non-Foster" term means it's an active antenna. The phys.org title implying some sort of breakthrough physics is click bait.
The acoustic antenna they design is passive and does not exceed the Chu limit, keeping in mind that the Chu limit accounts for the speed of propagation, i.e. light vs sound.
From the Paper, "We note that the demonstrated ME antennas are pure passive devices, no impedance matching circuit, or an external power source was used during the measurement. And its maximum achievable bandwidth is within Chu–Harrington limit (Method)"
The whole thing is really about their novel magnetic piezo material and device
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"100 times smaller" This is why we can have nice things in our tech headlines. The proper terminology is 1/100th and a hundredth of the size. Yes, we all know what it means, and its a common mistake, but that is no excuse.
sorry, just a peeve of mine.
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Metal membrane (Score:5, Informative)
Re:Metal membrane (Score:5, Interesting)
"It was very good for receiving'
Same could be said for the ubiquitous ferrite loop antennae used for AM broadcast reception. They are magnetic field devices that can be quite small (a few cm) compared to medium wave wavelengths of several hundred meters. They are great for reception, but pretty much useless for transmitting. They also have very narrow bandwidth,. have two very sharp nulls in their reception pattern, and work progressively more poorly as the frequency increases.
Sooo.... (Score:2)
Soo there really will be voices in my head?
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"Soo there really will be voices in my head?"
Only until the non-replaceable battery dies (or explodes).
Swap that ..... (Score:1, Informative)
Re:Swap that ..... Me too (Score:1)
Whoever did the write up is 180* out.. EM is the shorter wave ( hence the terms shortwave and microwave radio) and audio are the shorter waves .. but interesting concept
make that: Audio is the Longer wave (more physical distance between peaks).
Re:Swap that ..... Me too (Score:5, Informative)
Audio is the Longer wave (more physical distance between peaks)
Avoid the term "audio"; 60 MHz acoustic waves (as described in this paper) are not audible.
Sound (in any normal medium) is far slower than light, so sound waves at some frequency are much shorter than radio waves of the same frequency. They're describing antenna that oscillate acoustically at millions of hertz; the same frequency as the EM waves being received, not thousands of hertz as in audible sound.
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Sounds Like a Terrific Way to Kill Stealth (Score:5, Interesting)
If the wavelength is large enough, it becomes basically impossible to hide an aircraft with stealth shaping. So things like VHF radar will typically pick up stealth aircraft. So far the main issue has been that large wavelength antennas take up too much space precisely because of the limits explained in the article. If this stops being the case then VHF radars can be physically much smaller and portable and render stealth useless.
Sounds Like a Terrific Way to channel Stealth (Score:3, Interesting)
Part of shaping is that the reflected energy is AWAY from the transmitter. So you may see stealth designs that channel and eject in an upward manner where only aerial detectors may pick it up. There's also absorption. There could even be delays instead of hiding so that it may appear the target is further away from the receiver than it actually is.
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During the Kosovo War, the Serbs shot an F117 stealth fighter down. Turns out that F117s are visible to ancient long wavelength radar. Especially in wet weather. The unit that shot the aircraft down has regular reunions on March 27 that feature an F117 shaped cake..
Re:Sounds Like a Terrific Way to channel Stealth (Score:5, Informative)
The f-117 in question flew over the exact same mountain for three nights on it's route in. It had only one flying route in and out of serbia.
Anything can be done able if you wait for a good shot and only turn on your radar at the last second so they don't have time to evade.
Why does everyone always forget that part? The bombers had one mountain they were required to fly over as it was the only clear zone in from the neighboring countries who restricted what could fly where.
That brought down the plane as much as long wave radar
Re:Sounds Like a Terrific Way to channel Stealth (Score:4, Interesting)
Rubbish Journalism (Score:2)
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And sound goes at a few thousand meters per second... yeah it's rubbish allright.
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And sound goes at a few thousand meters per second...
Not in solids, generally.
yeah it's rubbish allright.
The real rubbish is your comment and its parent.
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Or your reading comprehension is simply rubbish. They're using EM vs acoustic of the same frequency, that's kind of the point.
And, since EM has the higher speed, it also has higher wavelength at a given frequency.
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When I read ... "an astounding 300,000,000 meters per second" I checked the source. "Science Mag". Maybe it should be Sciencey Mag.
Breakthrough for nano-probes? "Starshot"? (Score:3)
For those of you who read about that absolutely crazy idea to send chip-scale (or chip "mass", they may be very thin objects like a film) interstellar probes riding on gigawatt beams of laser light (that would accelerate them to .2C in a few hours!), "maybe" this helps solve a problem.
How do they communicate with Earth?
This might allow them to RECEIVE (over interstellar distances?) a very powerful signal even if they are very tiny. The only problem is, I don't see how they could SEND back data; in addition to antenna size don't you need power? (My knowledge of physics is woefully inadequate to evaluate this). Short of them carrying self-replicating nanobots that could construct a large antenna at the destination using local materials (and local power), I don't see how even having a good antenna would allow them to get a signal over trillions of kilometers with even an enormous (space-based) receiving antenna. Does anyone know how the Starshot project intended on sending a signal back?
On the other, for LOCAL communications (say for chip sized probes scattered over a wide area), this might be a key breakthrough. Imagine a carrier spacecraft with a powerful communications subsystem settling into orbit around say Titan. It spews hundreds (thousands?) of these little chips which, with a little protection/good surface/weight ratio might be able to gently break into Titan's thick atmosphere. Then, once on the "ground" (or floating in the Titan seas) they could communicate back to the orbiter which would then relay the observations back to Earth. (How to keep them powered in the low light/liquid nitrogen temperatures is an exercise left to the reader).
Or this could be great for surveillance (or spying) or wildlife cameras (or spying) or ingestible sensors/cameras (or spying)
As opposed to ... (Score:2)
... make antennas for wireless communication ...
As opposed to antennas for wired communication?
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Einstein Describes Radio (Score:2)
You see, wire telegraph is a kind of a very, very long cat. You pull his tail in New York and his head is meowing in Los Angeles. Do you understand this? And radio operates exactly the same way: you send signals here, they receive them there. The only difference is that there is no cat.
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Yes, you have. The conversion you mean is probably an audio signal modulated on a (much) higher fixed (unless modulation is FM) frequency EM signal. In that case, you receive the EM signal, separate the effects of the modulation by subtracting (filter, mix, whatever) the fixed EM signal and go on to recreate the audio according to the modulation used.
In this case, you convert an EM signal directly in its same frequency 'sound' equivalent. Because 'sound' (or pressure) waves travel slower (~340 m/s in averag
Transmission? (Score:2)
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You would be better off just standing on your roof and SHOUTING to the person that you wanted to call.
Sooooooo (Score:4, Funny)
So, next to feeling the EM waves of my WiFi router i will soon also be able to hear them.
I wonder what "they" will tell me to do....
I must be missing something here (Score:5, Interesting)
The antenna is 2 stage - it picks up the EM waves which essentially get converted into vibrations of the same frequency which are then converted in electircal signals. Ok, I get that. But I don't get how the EM waves make it vibrate in the first place and surely if the antenna is normally far too small to intercept the waves of a given frequency they'll just pass it by and nothing happens?
I'm obviously missing something here but RTFA article doesn't help and the nature document is a bit over my head. Can anyone explain whats going on in laymans terms?
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Take the obgoodoo and the bogoodoo and you have a revolutionary new gizmo that only works in the lab and will never be used in real life.
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Ok, I get that. But I don't get how the EM waves make it vibrate in the first place and surely if the antenna is normally far too small to intercept the waves of a given frequency they'll just pass it by and nothing happens?
Construction involves piezoelectric material, which changes shape according to the strength of electric field in which it is placed. It means that if you apply varying field, it will follow field changes with own shape change. The opposite holds true too: if you mechanically change the shape of an object having piezoelectric property, it will generate electric field.
The antenna doesn't need to be placed across the whole wave, it just needs to resonate with the rhythm of the change: when it contracts because
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They pick up the EM wave inefficiently (passively) at the start. It gets the antenna vibrating, which then increases its efficiency (now a non-Foster, active antenna) to thousands of times higher than normal.
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Brain implants are awesome and all (Score:3)
Sounds interesting (Score:2)
When will I be able to pick up such a TV antenna at my local Radio Shack?
spying (Score:2)
Keep them the same size. (Score:2)
joking
Re: The Republicans will never allow... (Score:4, Funny)
Correct. Improvements to batteries happen constantly but never make it to the people. To the people.
(STORED) POWER TO THE PEOPLE!!!
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