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10Gbps Wireless Transfers
Erasei writes "NTT Science and Core Technology Laboratory Group has developed a wireless communications that is capable of transmitting data at speeds of up to 10Gbps. In order to achieve such high data transmission speeds, the system uses the as-yet-unused 120GHz frequency band. The actual bandwidth the system uses is 17GHz, and the method of modulation employed is amplitude shift keying."
Yesterday there was an article about 19megabits.. now its 10gbps.. Wow, we are getting faster everyday!
A large number of birds seem to be falling out of the sky fully cooked near the NTT Science and Core Technology Laboratory Group headquarters near the experimental wireless data towers. More on this strange story as it develops.
May you be touched by His Noodly Appendage. RAmen.
I'm not thinking so much of a peer-to-peer or client/server setup where there's a networking handshake, but more along the lines of a broadcast data stream meant for everyone (or maybe just a few certain someones) to pick up.
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NTT Develops 10Gbps Wireless System
October 18, 2002 (TOKYO) -- NTT Science and Core Technology Laboratory Group has developed a wireless communications system using the 120GHz band.
The system, which is capable of transmitting data at speeds of up to 10Gbps, was displayed at the "NTT R&D Forum 2002" event held Oct. 11 in Atsugi.
The new system is four times as fast as the 2.5Gbps wireless system NTT put on show at the same event in 2001. This is the first time the laboratory experimented with a 10Gbps wireless system (photo). There are many potential uses for such a high-speed wireless technology, such as for 10Gbps wireless Ethernet links or for radio links between different buildings where a high volume of data has to be sent to and fro. NTT plans to announce the new system at the "Asia-Pacific Microwave Conference" (APMC) to be held in Kyoto in November.
In order to achieve such high data transmission speeds, the system uses the as-yet-unused 120GHz frequency band. The actual bandwidth the system uses is 17GHz, and the method of modulation employed is amplitude shift keying (ASK), the simplest method of amplitude modulation for digital signals. According to an NTT source, by modifying the modulation method, the throughput rate will be improved.
NTT also used optical communications technology to make the 120GHz system possible. A 120GHz optical pulse signal is generated, and then undergoes amplitude modulation. After modulation, the signal is picked up by a special photodiode capable of responding with the high-speed signal. The output from the photodiode is then transmitted as a wireless signal. The special photodiode used was developed with NTT's own technology, and can handle optical inputs of up to 300GHz.
The main difference between last year's system and the new one is that the receiver frequency detection circuitry has been redesigned, meaning that the receiver can detect signals over a wider bandwidth, and thus the system can operate at faster speeds. The new detection circuit can receive signals from an 8.5GHz band at maximum. Because the system employs two detection circuits working in tandem, the finished system realizes more than a 17GHz band.
At "NTT R&D Forum 2002," the system was shown transmitting non-compressed HDTV-quality (1.5Gbps) video data. In order to extend the range of the transmission, a 20cm-diameter lens was used to focus the beam. In the laboratory, a 10m range for the system has been confirmed, but NTT is expecting to try and extend the range to 100m.
In order to extend the range of the transmission, a 20cm-diameter lens was used to focus the beam. In the laboratory, a 10m range for the system has been confirmed, but NTT is expecting to try and extend the range to 100m
From a scientific standpoint, this is somewhat interesting. I don't see it being news, however, until they seriosuly decrease the size of the transmitters and/or increase the range. The transmitters look to be about the size of a shoebox, which is great for building-to-building, but let us know when they actually bump up the range to say... building-to-building distances.
Radio waves at 120GHZ travel like light. The signal wont go through walls at all.
So, basically, what we're saying is, by the time we get to 1Tb/s, we're all going to have to be close enough that I might as well just hand you a floppy?
And is that a run-on? Sheesh. Critics.
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"In the laboratory, a 10m range for the system has been confirmed, but NTT is expecting to try and extend the range to 100m."
10 meters would limit its usefulness, but 100 meters would make this very useful. Hopefully, this has a useful range.
Could someone answer the question about how easily this frequency would pass through common substances, like walls?
Also, there was no mention of weather they would seek to license their technology to make this widely available or just make this a very expensive specialized niche product.
This isn't office wireless. This is a very line-of-sight system that would be used, probably, between buildings, if they get it go that far, I would imagine.
You'd never see anything like this in a home or office, as it couldn't penetrate a sheet of paper, let alone a wall of any type. I suppose it could penetrate if you put enough power into it, but then it would need enough power to melt through the wall before the communication could begin.
I'm no EE, but I studied enough analog electronics design to know that creating RF circuits at that kind of frequency is no easy feat.
Open up an 802.11 card for instance--these work at about 1/60th of that frequency--and look at the traces for an idea. It's not just what components are connected together--it's the layout of the traces that define most of the circuit. Inductors are little squiggles, a resistor is the thinning of a trace, etc., all of which is highly dependent on frequency.
In other words, these guys are pretty slick and you just have to bow to them.
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120Ghz? I can not think of an op-amp that works anywhere near the freq. Not to mention a waveguide to get your output to the antenna.
As for omnidirectional, that would lower your effective point to point power further.
At these freq's it could only be useful for point-to-point comms.
I wonder why they did not just leave it all optical.
The law is a weapon of the government, not a protection for the likes of you. Surely you understand that.
Actually I'm hoping to transmit from the desk to the object sitting at the desk...
My current device uses the 560nm-800nm electromagentic spectrum. And while it can send a large volume of data quickly, my receiving unit processes the data, but most it is lost in storage. If only the process wasn't so lossy!
Can anyone recommend any upgrades? I am still using the orginal neural network that came with this model...
(too subtle?)
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not to mention (i'm guessing) a hella lot more range,
You guessed wrong. The range goes down as the frequency goes up. The higher the frequency, the more the radiation behaves like light, which is really just terahertz radio. As you get higher and higher frequencies, walls and such become more and more opaque to the signals. Until eventually they won't travel thru the walls at all, just like light.
If you want long range, you need lower frequencies. If you want to send a signal across the ocean, you need KHz radio waves (short wave radio). If you want to send a signal around the state you need AM radio at ~1MHz. If you want to send your signal around a city you can use FM at ~100MHz. By the time you get up to 2.4GHz you can only send your signal across a few rooms. Yes, I know I'm simplifying the differences in transmission power. But a short wave ham can reach across the world with less power than an AM station uses to cover a state, and the AM station uses less power still than the FM station which only covers a city or so.
Now, point to point is a whole different story. If you have direct line of sight you can send extremely high frequencies across significant distances. But the curvature of the Earth prevents you from sending stuff too far. Not to mention buildings and other obstructions.
That's what I want to know. IR is way up in the THz range. You outta be able to modulate a least a Gbps onto it easily. Sure, it wouldn't go very far but so what. Is it just the difficulty in making emitters and detecters which are fast enough? That can't really be that hard. A gige optical SX GBIC module can be had for under $100. Hm. That makes me want to tear a couple apart and see if I can get a link running across a few feet of free space.