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More Antennas, Faster Wireless
rouge86 writes "The New Scientist has a story on how researchers broke the network speed record using a wireless network and multiple antennas. They plan to use the demonstration to show how powerful multiple antennas can be. Applications include power saving on mobile phones and reducing interference."
This is just another sign that wireless is replacing wired networks around the world. I'm guessing sometime in the near future wireless will outnumber wired networks. I think that everyone can be excited about this.
Power saving is very welcome indeed. Today's 3G phones run out of battery in no-time.
siemens broke the record blabla 1 Gbps wireless
For those who don't care about reading the entire article, the crux of it is:
Recombining smaller signals in real time, however, requires considerable computing power. So the Siemens team developed new computer algorithms in order to send more data using existing hardware.
In short: programmers managed to push existing hardware with a more efficient code. That's called hacking, albeit with a serious look, and I like that!
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
...that TV antennas from the 1950's used? Greater surface area = better reception?
this is the same post, as the dec 08 slashdot post here: http://slashdot.org/article.pl?sid=04/12/08/022625 0&from=rss/
OFDM has been around for a while OFDM History
It's nice to see more practical uses of it in wireless standards like WiFi IEEE 802.11a, 802.11g and in WiMax IEEE 802.16a.
All this adds up to the death of the control by telco's in the last 100 yards of net connectivity. Go OFDM!!
Quidquid latine dictum sit altum viditur
Since the improvement was mainly a hack on the processing.. I'd guess that they went from some sort of fourier transform to wavelets.. wavelets have linear computational complexity (awesome) and don't have the interference problems that older signal processing algorithms have.
Is anyone else making the comparison between "more antennas=better" and the mach 3 razor "more blades=better"?
Wouldn't increasing the amount of antennai per device reduce the overall maximum supported device in the broadcast range?
...now I have to buy a new phone again.
How am I supposed to fit a pithy, relevant quote into 120 characters?
Adding more antennas increases the signal-to-noise ratio. More signal, less noise, reduces the bit error rate.
This isn't news.
Unfortunately, Beijing has often jammed the signal. This new antenna technology may be a good way for the Tibetans to evade jamming. How can we build a special radio that uses a miniature antenna array?
And increasing it for the neighbour, unless he also has multiple antennas.
Wich gets us back to the start, only with even more interference...
Hivemind harvest in progress..
"All this adds up to the death of the control by telco's in the last 100 yards of net connectivity. Go OFDM!!"
Doesn't matter if you control the pipe at the spigot end, or the pump end. Control is control, and they're still going to get there cut. Just as cellphones doesn't remove them from the picture. Same with VoIP. You want telco's completely out of the picture? Control everything from one end to the other, and make certain they don't have a financial stake in you.
Now we can be sure of getting cancer
/Spoken by a nuclear engineer
Porcupines discovered this way before these researchers did.
Banu
"10^100 blades, each only a single atom thick" -they would fuse into a single blade- Now a two dimensional blade- that would shave your face right off! - shave only once, and never shave again!
"The other side of this is that some people who understand how to make antennas had to figure out a compact array of antennas which would not need any sort of calibration and which would provide the necessary hardware to even use this software signal processing technique. Those are the people that really impress me, because I am horrible with mathematics."
Fractal Antennas. Anyway, thanks, but when it comes down to it. It's all math. It's just the realm it eventually ends up living in.
Its not the size of your antenna, its the number you have??
This comment does not represent the views or opinions of the user.
Its just so fantastic to be able to break into a network in a few moments and be on your way to a big payoff through corporate espionage with next to no work. You just have to love how technology is adopted in critical areas well before anyone has got off their ass to learn how to do it right.
"I use a Mac because I'm just better than you are."
Of course, this means more fodder for us wardrivers -- more antennas mean more UINs to map!
Zhrodague.net - I do projects and stuff too.
"Porcupines discovered this way before these researchers did."
Uh huh. So were can I buy my porcupine Wi-Fi receiver?
Have to burst your bubble, but I'm in the middle of Kansas. There's no mesh to join up.
Second, science (and it's stepchild, technology) appears to be the new faith. Whatever's ailing humanity appears to be solvable, if you believe hard enough in science.
Eventually we'll all be nice to each other due to the implanted N.I.C.E. chips in our brains.
The article doesnt say how long(distance) it was transfered over...
Surely you can get greater speeds the closer you go, but when you hear about LAN speed records they generally specify a distance, this they dont. and as we all know the further from the AP the worse the signal. Where they standing right next to the AP?
http://www.thegreynomads.com
It's mathematics and a solid understanding of signal propagation that made the antennas possible.
It's mathematics and tuning of the algorithms used to work through that mathematics that made the DSP firmware possible. You have to thoroughly understand the math behind the DSP stuff to optimize it right.
Just because there's code involved, doesn't mean that there were just code-monkeys doing the work.
I am not merely a "consumer" or a "taxpayer". I am a Citizen of the State of Texas
OFDM has nothing to do with mulitple antenae. You can send OFDM signals across a channel with a single RX and TX antena. OFDM is simply a convinient way to turn a freq-selective fading channel into multiple, independent flat fading channels by interpreting the data as the IFFT of the TX signal. Spreading the data out over frequency can be used to get good diversity and thus avoid bad fades.
Using multiple antenae is also a good way to get diversity in a way that complements OFDM (spatial vs. freqency). More diversity in an RF channel is almost always good. The exception is when it forces you to spread your energy over multiple sources too mutch. However multiple RX antena don't increase energy use, instead they just absorb more energy, and in a manner that is better than a single antena with twice the gain. This is because while one antena may be in a bad fade (a destructive multipath null), chances are much lower that both will be in a bad fade.
Multiple TX antenae can be used too, but the implementation (and decoding) gets mutch more complex as the article suggests: you need lots of computing power to grab the bits out of multiple simultaneous (but cooperating) TX sources. You also spread your energy with multiple TX antenae, which lowers overall SNR.
"You saved 1968." - Ms. Valerie Pringle to the crew of Apollo 8
I learnt a couple of years ago in Telecommunications class about the benefit of more than one antenna for wireless communications. Maybe the big deal is that products are starting to come out to the market. The technology however, is nothing new.
I see nothing new in this principle - anyone knows that more aerials are better - in fact, if you increase the number of aerials so that their combined length (l) matches the exact distance between the sender and the receiver (ie: l = d), AND then you place each aerial in and end-to-end configuration so that electrons can flow in an unbroken path from transmitter to receiver then you have a very efficient data transmission medium - heck, the principle even works with optical fibre and photons too.
AT&ROFLMAO
With all their antennas :D
I would think that a mean network would be the 802.11b network running 11MBits, not 50. Are there really that many 802.11g networks out there, pushing the average up to 50, or is this reporter just clueless because their office runs around 50? I used to travel quite a bit, and what networks I did run into at coffee shops and airports were 11 Mbit. Do others have a different view than this?
Great ideas often receive violent opposition from mediocre minds. - Albert Einstein
so now i need six more pringles cans for my end alone?
...I got nothing.
This is slightly off this topic, but in the wireless realm.
How do I go about boosting my reception with an antenna...a la pringles can? Specifically, is it possible with an internal laptop wireless card?
Or is it possible to boost my router's pickup?
Any websites or advice would be appreciated...thanks!
[I can picture a world without war, without hate. I can picture us attacking that world, because they'd never expect it]
So we replace wires with wireless but double up on the amount of terminated wires (ie antenna's), cute. Aint you all glad somebody never put a RS232 on the back of a microwave oven, as I'm sure somebody would convert it into a crude basestation :)
So we get rid of all the wiring inside and terminated it on the outside a few doxen times instead and coat in plastic, and people get upset about mobile phone masts, boy are they in for a new shock soon when Joe Smith turns his house into a hedgehog array.
we all turn into Radioactive man. Or should I say... cancer man
- There's no place like 127.0.0.1
Screw wireless data, there's enough of that already. (Sure, there's always room to improve, but what we have works for most purposes.) What I miss is wireless power!
:-(
Wireless can reduce the cable clutter by eliminating the Ethernet cable and the keyboard and mouse cables, but you still have to power there things, so you either periodically change batteries or recharge them, and thus you either spend money and time, or you forget to recharge and lose even more time.
It's nice that you can bring your notebook to the office and work on the network without plugging it in, but try working like that for eight hours! You still have to plug in.
I wonder when someone will invent a useful wireless power source...
...for standardization as 802.11n
Proposals were submitted back in August for 802.11n, and all proposals still in the running use MIMO+OFDM (the technique described here). Hardware supporting various prototypes is already around in a usable form.
It seems unlikely that 3x4 MIMO will be around in the first wave, due to cost constraints - 2x3 (2 tx, 3 rx) is the most likely initial configuration.
This reeks of channel-bonding to me. How (if it is) is this different?
Interesting, the same technology is used in Airgo Networks' True MIMO but it seems they can reach only 40-50Mbit/s. The "interesting" part is that it gives you still 10-15Mbit/s 120meters far away the house (with the router inside). So, time of cantennas is over? The bad news are these company's declarations: "Pre-n is shorthand for "Wi-Fi compatible 802.11a/b/g products that offer MIMO OFDM extensions. Pre-n gives the significant benefits of 802.11n along with Wi-Fi compatibility today. Pre-n does not mean interoperability with future 11n products in the 11n modes." I hope Siemens' 1Gbps would be inside a real standard and not some strange/inconsistent private implementation like modern "2X" wifi technologies
Yes, faster network == faster spam! Just what I needed. Now I'll need a faster CPU in my cell phone to delete those spam messages. Probably multiple networks, maybe even the potential for the phone to be a spam relay.
We can't disparage the telco's control too much. Though tyranical at times, there is a financial backbone that we don't want to break. We're pushing for a Marxian revolt on the telco's to go Robin Hood on internet bandwidth, but we're griping at an alarming rate about IT jobs going overseas and jobs being lost in the IT sector. We want the technology, but we don't want to pay for it...people want what you make at your job for free too.
This is the same entitlement scenario that was looked at with MP3s and the iPod years back. Internet bandwidth was funded by someone. Music was created by someone. We think we're entitled to anything that can possibly be accessed for free just on the principle of the matter. To conceptualize - on the day you can give away your own job services for free, start demanding free internet and music.
Link those networks together!
http://www.wiana.org
Now given to options pay nothing and get say 100th the bandwith or pay 50$ an month and get full bandwith most people are going to opt for spending cash
NetZero: $10/mo for 48 kbps. Comcast: $46/mo for 3000 kbps. Trust me, people will put up with 1/60 the speed to save cash. And are you sure it'll be 1/100 the bandwidth, or just 100 times the latency?
So unless the mesh networks start having servaces that the ISP wish to connect to your not going to see mesh networks making the internet free.
Some universities will have both Internet and Meshnet. Watch students set up gateways as a class project.