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Airgo Quadruples Wi-Fi Limit
QED writes "Airgo Networks, a privately held maker of wireless networking components, said on Wednesday it has developed chips that will increase the Wi-Fi speed limit by a factor of four.
The Palo Alto, California-based company, which designs its chipsets around Multiple Input and Multiple Output (MIMO), a wireless technique that uses different radio channels to improve both speed and transmission quality, said it has achieved data rates up to 240 megabits per second (Mbps)... "
... I need better distance and fewer signal dropouts. I'm not talking about all that far distances either, just 200-300 feet inside an office building with many sheetrock walls and twisty hallways.
So, in other words, they've developed a chipset that will allow a router/WAP + WLAN card to use multiple channels at once...
Not only is that not -really- upping the bandwidth limit (they just got more signals, not a bigger throughput per signal), it seems to me that it'd blast out 1/3 - 1/2 of the avaialble spectrum within range for wireless.....which means if you buy one and are in an apartment/city/whatever, you could be a real jackass to your neighbors simply by using it...
Wow. Ok, I'm not great on the conversions, but isn't 240 megabits/second = 30 megaBytes per second? If that's really the case, I don't think data can even be written to my hard drive that fast. Wow.
Tech, life, family, faith: Give me a visit
I don't understand the way wireless speeds are rated. I got very close to 100mbps on my LAN before I upgraded to gigabit. I can't get anywhere near 54mbps on my wireless if I put my Powerbook right next to the wireless router!
I'm not certain, but I think the word channel may be misleading here. I think that MIMO is actually using the same bandwidth, just combining multiple RF paths to enhance the signal to noise ratio. Another MIMO link is here.
Good point, but for some of us there would be a big benefit with higher wireless speeds. My cable modem has a typical download speed of 3Mbps so even the 11Mbps (max) speed of 802.11b isn't being used to its full capacity. But I often need to move large files between my laptop and my PC. If I don't want to wait 10 minutes or more for a file transfer I have to carry my laptop into my home office, plug it into my Ethernet switch and transfer the files there. With faster Wi-Fi I could avoid this minor hassle.
Quantum mechanics: the dreams that stuff is made of.
That a great way to be a good neighbor. Piss all over all the channels available so no one else can do anything.
I was about to post with the same sentiment until I read more on the tech.
MIMO is not your typical blast-it-on-multiple channels approach. This article discusses the technology. Instead of using up a bunch of channels, MIMO systems send multiple signals on one channel and use multiple antennas and advanced algorithms on both ends to sort out which signal came from or went which direction.
Two wrongs don't make a right, but three lefts do.
4x the speed is still not that great.
Current 802.11g devices have a theoretical throughput of 54mbit, and a real-world throughput of actual data of 10 to 20mbit. So it follows that Airgo's new cards will permit 40 to 80 megabits.
Now, wired 100mbit networks can reach 80mbit real-world speeds (Actual after-overhead bandwidth), so at first glance it looks like we're there. Except we're not.
The important things to keep in mind is that wireless networks behave like hubs, not switches, and on top of that all data must go through the access point. So if you have two computers close to an AP, you take up 40mbit for computer -> AP, and the other 40mbit for AP -> computer.
In other words, they claim 240mbit, but the fastest real-world transfer between two wireless devices is probably about 40mbit, IF those computers are very close to the access point. If the computers are a bit further away, you will get 20mbit. 4 computers doing 2 transfers and each transfer goes at 10mbit.
So you see? 4 computers 50 feet away and you're already down from 240mbit to 10mbit. This is very far away from wired performance.
To put this in software terms, They are multithreading the connection.
-Rick
"Most people in the U.S. wouldn't know they live in a tyrannical state if it walked up and grabbed their junk." - MyFirs
Wireless will continue to improve indefinitely, and is likely to retain a degree of backward compatability. Like any developing technology, you should ask yourself what's going to be useful to you for the next few years, and adopt it.
If you had made this decision four years ago, decided 802.11b was "right for you", and bought 802.11b cards, you'd still be in the position today that you can find compatable, cheap, equipment that'll suit your needs.
The only case where there's no direct backwards compatability is for 802.11a, and that's because 'a' works on a different frequency. But you can buy 802.11abg WAPs, they're a little more expensive than regular WAPs, but once you have your WAP, you can buy any equipment you need to go with it. Additionally, nothing stops you from buying additional WAPs implementing different standards in the future (they can all connect to the same Ethernet network)
Long term, you may increasingly have to replace equipment anyway. Your 486 probably will not run Windows XP. But the 486 will still work, still run 95 and GNU/Linux, and all the other things it did when you bought it. Likewise, your 802.11a WAP will still allow all the machines you bought 802.11a cards for to use your network. If they become scarce, you can think about buying a newer WAP, and have your newer hardware use that.
You are not alone. This is not normal. None of this is normal.
Airgo is a participant in one of two consortiums of companies promoting competing technologies to use in the 802.11n standard. Here's an article that covers the situation:
t icle/CA445702
http://www.reed-electronics.com/electronicnews/ar
Airgo is obviously trying to gain leverage with their technology by getting it out on the market early. I don't think this is a good thing in the long run, since we all have benefitted by the degree of standardization in 802.11b/g and Airgo seems to be trying to get their own proprietary technology out there in front of the legitimate standards process.
-R
In the MIMO system they're discussing here, you use the same frequency bandwidth but deploy multiple antennas, which gives you spatial diversity. Wireless communications are basically limited by the probability that your channel goes screwy and experiences what's called a fading event, where your signal suddenly drops because of interference. This means you have to be more conservative in the data rate you transmit at.
What they're trying to do is transmit, receive, and resolve multiple signals in the same frequency band by using multiple antennas, and resolving them in a clever way to try to create independent data channels. Since each antenna is physically at a separate location, the signal paths (and hence the fading characteristics) from the transmitter to the receiver will be more independent. Then the odds that all channels experience fading simultaneously drops significantly, improving the overall robustness of your communication channel to fading. That means you can be less conservative and achieve higher bit rates through your channel.
In short, same frequency usage, but they're getting spatial diversity by using more antennas and giving themselves a more robust channel.
The bold print giveth, and the fine print taketh away