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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...
When will the wireless market begin to stabilize? I will not invest in wireless technology that very well may become out of date or unsupported by newer hardware in the near future. As such, I will continue to use gigabit ethernet, thank you very much.
Cyric Zndovzny at your service.
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
Huh? How would being able to switch to a different base station affect the fact that your neighbor is taking up too many channels for your computer to get a word in edgewise?
This trick, along with the 108Mbps networking that's already on store shelves, is an abuse of the standard and should be avoided for the common good. There's always a huge uproar when some company is caught using an unsanctioned extension to a software protocol; this situation is no different.
no pun existed.
useless sig advice - Read Nabokov.
and the distance is... ?
Yes, I RTFA and didn't see it. I know enough about MIMO to know that it's great, but until we've come up with a way to comfortably blanket the world in a massive wireless network, bandwidth isn't a big deal.
IMHO, 802.11s is where the funding should be. It is right now for the most part, but more could be spent.
For more info on the available protocols:
http://en.wikipedia.org/wiki/IEEE_802.11
Based on what the release says, I think it uses as many as four or five different channels. MIMO really only provides increased signal to noise and helps manage and utilize multipath. In and of itself, it doesn't provide a speed boost.
Yes the article is confusing. But I'm afraid you're wrong on two counts.
First: Even if all it did was improve the signal-to-noise ratio it would boost the speed - because you can trade away better signal-to-noise ratio for more bits - tightening modulation constelations to send more bits in the first place and/or lowering the overhead for error correction.
But MIMO also uses "spatial diversity" to get additional genuine bandwidth between the transmitter and receiver. Signals from different antennas add and cancel differently at different locations. So generating a set of several signals coherently (using a common clocking source so they maintain a stable phase relationship) and distributing them differently over several spatially separated transmitting antennas - then receiving them by several spacially separated receiving antennas, your receiver can sort them out again. If you have M transmitting and N receiving antennas you can end up multiplying the amount of data you can send by the smaller of M or N.
It's like sending morse with a flashlight and receiving it with a photocell. You can only modulate the flashlight so fast. But if you have an array of flashlights each sending separate morse streams, and an array of photocells at the image plane of a telescope, you can send as many times that much data as you have flashlights/photocells.
You're doing coherent-wave hacks to make your telescope imaging mechanism out of the antennas themselves - generating virtual antennas pointed differently and virtual "light sources" spread out and overlapping in varied (but sort-out-able) ways. But the effect is the same.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
(In full disclosure I did some work with Airgo in 2001 and early 2002, and earned some stock options as a result of that work. Having said that, I haven't had any insider access since that time, which was well, well before they were shipping any product. In fact, I'm so out of the loop that this announcement came as a complete surprise to me, as did their previous announcements that companies were shipping products using their chips.)
I design wireless networks and hardware for a living.
Which makes your lack of knowledge about this stuff a little more disappointing.
not to mention that the algorithm they're probably using only works because 802.11 has fairness problems, will definitely conflict with 802.11n (which also uses MIMO), and has a kook for a CEO.
The cheap personal shot at Mr. Raleigh notwithstanding, you are aware, are you not, that Airgo is one of the primary drivers of the 802.11n standard? This is an extension of the work they are putting into that standard, in fact, and which they are already selling in 802.11-pren products manufactured and sold by Linksys, Belkin, and so forth.
This guy is talking about something no more complex than using four radios at once and he's talking like it's the Second Coming.
MIMO is a heck of a lot more than just using four radios and combining their data rates together. This is about exploiting multipath to improve spectral efficiencies without widening the channel bandwidth.
Other people, who DON'T claim to design wireless hardware, I can forgive for not seeing that this article does a poor job of explaining what MIMO is. You should know better than to assume that they're trying to pass off simple channel bonding as MIMO, if you're really in the business.
Could someone please bonk him with a hardbound copy of the 802.11n standard?
Given he and his cohorts wrote a big chunk of it, I don't think that will be necessary.
This is pre-802.11n stuff, folks.
No, it is actually post-802.11n stuff. They already have their fingers in the 802.11 pie. What this may be, in fact, is an attempt to sway the standards body towards a standard that more closely hews to the Airgo approach, by demonstrating its scalability.
Wait for the real stuff to come out from established vendors who actually contributed to the standard,
That would include Airgo, actually.