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Scientists Twist Radio Beams To Send Data At 32 Gigabits Per Second
concertina226 writes Scientists from three international universities have succeeded in twisting radio beams in order to transfer data at the speed of 32 gigabits per second, which is 30 times faster than 4G LTE wireless technology in use today. The researchers, led by Alan Willner, an electrical engineering professor with the University of Southern California Viterbi School of Engineering, successfully demonstrated data transmission rates of 32 gigabits per second across 2.5m of free space in a basement laboratory.
Something tells me it's probably like +80dB, while real world conditions will expect -40dB. :-)
Should have used optical fibre.
the University of Southern California Viterbi School of Engineering, successfully demonstrated data transmission rates of 32 gigabits per second across 2.5m of free space in a basement laboratory.
They would have tried for 10m, but Mom and Dad told them that the street lights were on, and their little friends would have come up from the basement and go home.
Yeah, I could do with one of those office-space meme's right now.
If all the nay-sayers faux-gasping at the extreme length of 2.5m could shut up, that'd be great.
I'm not sure what people expect these days - this is a major achievement - whether it *can* be extended, or whether it *will* be extended would be different achievements. You could almost apply Jackson's rules of optimisation to this (refresher below) - in that first you *do* it, and only then (if you're an expert) do you try to do it *well*.
Simon
Jackson's rules of optimisation: "The First Rule of Program Optimization: Don't do it. The Second Rule of Program Optimization (for experts only!): Don't do it yet."
Physicists get Hadrons!
transfer data at the speed of 32 gigabits per second, which is 30 times faster than 4G LTE wireless technology in use today.
Exactly which carrier offers gigabit 4G LTE?
Some 4G implementations have a theoretical upper limit of 1 Gb/s for low-mobility agents.
http://en.wikipedia.org/wiki/4...
If it weren't for deadlines, nothing would be late.
I notice from the diagram (per the linked story) that I only need to fit a spiral phase plate (no, not a flux capacitor) to my Tardis and it all works automagically...
... via "orbital angular momentum" and "OAM multiplexing".
Frankly, I am still confused as to why it's not (more simply) "circular polarisation" that has been known about since the early days of radio.
Looking at space, radio, science and computing from a 'down-under' amateur enthusiast perspective.
How long until it is used as a medium for porn? lol.
what do you think the data sent as a test was...
---Saying gnome 3 is better than windows 8 not so much a compliment as it is damning with light praise.
The reference to 4G limits has exactly what to do with this story? This was not 32Gb/s over a 4G network, it was 32Gb/s over an unknown protocol at a very short distance. I'm guessing that the basement was isolated from signal noise, which means this pretty much a non story or extremely premature.
There are many people that invent some batshit crazy things that simply don't work in the real world. Honestly that is not an insult directed at the inventors, because their work tends to lead to other developments down the road. It's more an insult at media which focuses on hyping everything possible.
-The wise argue that there are few absolutes, the fool argues that there are no probabilities.
Raw 4K video. Even at the current distance, this could be used for a purely wireless 4K display that supports higher than 8-bit/channel for better quality imaging all around.
Well, there seems to be a lot of information missing, but I'm suspecting that when they talk about twisting the radio signal they don't just mean static circular polarization, they mean that they are dynamically twisting it variable amounts as a way to modulate the data signal onto it. This would be similar to the modulation techniques used back in the last millennium to squeeze far more data down an audio like than the audio bandwidth would imply could be transmitted.
I'm an American. I love this country and the freedoms that we used to have.
It's been shown that all these "helical" polarization schemes are degenerate forms of MIMO essentially, and can't achieve speeds better then what MIMO antenna configurations can.
At short distances in quiet environments, you can do a heck of a lot which will never, ever work anywhere but in that experiment.
from the diagram, it looks to be a directional antennae.
if you are doing that with radio waves... why not a laser?
It's not a typo if you understood the meaning!
It's still modulation, modulation creates sidebands, and sidebands require bandwidth.
Nothing has changed, the Shannon–Hartley theorem still rules.
Along with IR and Visible light, unless you are pumping watts into a very small volume you're not going to boil your guts with wifi.
Dear aunt, let's set so double the killer delete select all
Nice diagram of a left-facing swastika in the article - or is that a southern-hemisphere hurricane?
Now they can have customers chew through their 1GB data cap in 1/4 of a second! Before you realise you're downloading something, it's wasted all your data.
The RAM in my laptop?
This is a myth. There is nothing special about 2.4 GHz as far as water is concerned. There is a mild absorption peak at 24 GHz, but nothing at 2.4.
The reference to 4G limits has exactly what to do with this story?
I suppose about as much as a Space Shuttle has to do with a person standing next to it. I took it as a scale-comparison, but I understand your point about the story creating a potentially false impression that this is an evolution of 4G.
If it weren't for deadlines, nothing would be late.
"which is 30 times faster than 4G LTE wireless technology in use today."
Hey, there are old grandmothers out there 30 times faster than 4G LTE. Still a long walk to Mars.
*Repent!Quit Your Job!Slack Off!The World Ends Tomorrow and You May Die!
Yeah, more politics! Less of that nerdy tech stuff! What do they think we are, a bunch of geeks who get excited by things like communications technologies and networking?
You are not alone. This is not normal. None of this is normal.
Yea, you gotta be careful. 1 watt of absorbed energy might heat your tissue by up to 0.001 F.
The reference to 4G helped put the speed in perspective for readers to better understand how fast 32Gb/s is.
Dr. Egon Spengler: There's something very important I forgot to tell you.
Dr. Peter Venkman: What?
Dr. Egon Spengler: Don't cross the streams.
Dr. Peter Venkman: Why?
Dr. Egon Spengler: It would be bad.
Dr. Peter Venkman: I'm fuzzy on the whole good/bad thing. What do you mean, "bad"?
Dr. Egon Spengler: Try to imagine all life as you know it stopping instantaneously and every molecule in your body exploding at the speed of light.
Dr Ray Stantz: Total protonic reversal.
Dr. Peter Venkman: Right. That's bad. Okay. All right. Important safety tip. Thanks, Egon.
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The structure in such transmissions drops of with distance really fast since it has a lot of higher order structure than just waves coming out of a dipole.
And just to really get people excited, you can give the signal another "twist", and another, and another - "HEY! It looks like we can achieve infinite bandwidth!!"
Along with using infinite spectrum and requiring infinite power
This really isn't anything all that new. Hams have been using phase change modes for around 15 years now. Some of these modes, like PSK-31, allow worldwide communications using tiny amounts of power.
But see that "31"? That's the baud rate. It was chosen because that is about the rate that a decent typist can type. Mighty slow.
But it's all scalable, There are much higher rates available. But they all have a price of bandwidth, and the signal needs to be all that much better. Read that as higher transmitting power. There are a few really clever modes, like "MultiPSK, which achieve a higher transmission rate by multiple 2 phase transmissions. They require less power to transmit, but take up some more bandwidth, and the software is more complex because all the separate signals have to be recombined.
The biggest ability of these "OhmaGawd" super transmission systems we hear about a few times a year is to attract dollars for more research.
Final? The system can work as long as they don't try to stuff too much into it. But I doubt in the present day form. Think a big increase in the number of cell towers, an overhaul of wi-fi devices. Note: I haven't seen the bandwidth needed, so am not certain, but this might mean less available channels for wifi devices.
No free lunch here kids.
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
Senior Lead Astronaut, that would impress even chicks.
"Contrary to popular belief, UNIX is user friendly. It just happens to be selective on who it makes friendship with"
And the implied point is the same: 60 dB away from practical means a factor of million improvement is still needed.
I come here for the love
This is like QAM? I recall back in the late 1980's some AM broadcasters had played around with Quadrature Amplitude Modulation. In essence twisting the phase of the carrier around to get channeling, etc.
Interesting and a good start but . . .
(Hard to tell clearly from the two articles but) these seem to use feed horns of a specific design and configuration (microwave transmissions usually do), that must be POINTED AT the receiver feed horn, so . . . if anyone is planning on "just plopping down the laptop" in any old orientation . . . it won't line up the transmission signals. Sure, for a trunk line between sites (buildings/planets) where critical alignment can be achieved . . . it'll work fine.
And some of the comments below seem confused . . . its not "faster" . . . its a "bigger pipeline". If it takes (on average, depending on planet position) 12.5 minutes for a signal to "reach mars" . . . it will still take 12.5 minutes. The signal won't "go faster" to get there in 6 minutes. When they say "faster" they mean . . . once the signal crosses the 12.5 minute distance . . . you can pump a higher bandwidth of data on that signal. But we won't be using this for "live control" of something like a Mars Rover. That's not the "faster" they mean.
Also, in terms of the "don't need USB cables any more, just put them close to the computer" . . . so, next time I enter the datacenter, I won't have to actually sneak in a USB thumb drive to tap the servers and steal data . . . I can just "walk nearby" and tap in? Sounds like a path ripe for exploitation. I know, its not that simple, and theoretically we can "tap into" keystroke/mouse streams that are RF now . . . but a USB "tap" seems more capable of nefarious activity than just a keyboard sniffer.
And I'd agree with the one point . . . (just like regular WiFi) other factors come into play and the high rate will drop off fast with distance . . . still. Always good to push the envelope . . . congratz all around to the dev's.
No, I don't remember your name. But the memory mapped screen on a TRS80 from 1977 is from 15360 to 16383 if that helps.
No, it wasn't. Most people here know how fast 32Gb/s is. In fact most of us work with, or on, gear that may not be wireless, but is much faster than 32Gb/s.
-The wise argue that there are few absolutes, the fool argues that there are no probabilities.
Ahhh...the goal of continuous, direct-to-brain, high quality porn streams continue to be driven apace.
Excellent.
(-1: Post disagrees with my already-settled worldview) is not a valid mod option.
While it may be argued that circular polarization is another MIMO scheme, it CAN achieve better speeds, because it DOESN'T REQUIRE EXTRA CHANNELS. MIMO, generally, does. There's nothing 'degenerate' about the relationship of the two schemes.
The real limitation here, is that this is a beam technology, it isn't for broadcast (i.e. you have to aim the sender and receiver antennae). The article mentions a 'phase plate', which implies the beam is directed perpendicular to the plane of that plate...
The real benefit, is that you get a factor of two without using any extra bandwidth from the available RF allocation.
Let's see. Assume body weight is 75kg, and 65% of that is water, for 48.75kg water or 48750g. 1 watt-hour = 860 calories, enough to raise the temperature of the water 0.018 degrees Celsius. The extra heat would then spread to the rest of the tissues, leaving the entire body an average of 0.011 degrees warmer.
Better?
Add a one and two zeros onto that and well be in business!
Fuckers
You were wrong. Accept it and move on, Senior System Engineer/Architect/Asshat.
zmodem was SUCH an improvement over xmodem. The ability to re-start interrupted transfers brings a smile of relief to my face thinking about it to this day.