Broadcom and Quantenna in Arms Race to Speed Up Wi-Fi Data Rates

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gordon_tron

Today there single band, 2.4ghz only, and dual band routers, one 2.4ghz and one 5ghz. Sounds like they are adding a second 5ghz radio, for a total of 3 wifi radios in a router... so, the "revolution" here is to reduce interference by using 3 wifi channels instead of 1 or 2?? My devices can only connect to one wifi at at time. To get the "on the box" max rate... do I have to buy two of these $200+ routers and connect them to each other? But I dont surf the internet or watch movies on the back of my router. What is revolutionary here? Hey, why not have a wifi access point on every single channel in the house? Wakeup call... if you have a wifi interference problem, its most likely not your home network (you to you), its your neighbors to you. Forget that your neighbors will have to do the same thing to compete with you, and their neighbors.. and before we know it the 5ghz band will also be trashed like 2.4. Wake up broadcom, Mu-mimo is revolutionary. It's getting more data out of a single channel, being able to transmit to multiple devices at once..Galaxy S5 will have it, other devices will have it by end of year. Getting mu-mimo into a router is what will reduce interference and improve wifi, no adding more wifi AP radios to each home. Seems like broadcom is worried about not having mu-mimo if they feel like they have to trash it... and in response just trying to cram more of what they already have into another flagship router, getting a yet bigger number no one can really use.

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Hey.That_Dude

I don't know if you're just being feed shovel and eat it up or if you did any research and got shovel there...

There are no "2.4ghz/5Ghz" antennas. You can use an antenna and get both channels. However, frequency "channels" and channels of bandwidth within the frequency range are different. In fact, frequency channels are called Bands, hence the terms "single band" and "dual band". Adding more antenna allows for more sending of information and results in a higher SNR (if you're using MIMO) for the receiver (also if it has a very good DSP and doesn't move too much). Mu-MIMO is just an extension of of MIMO (which benefits from more antenna) and thus it should also benefit from more antenna. More antenna, more streams, more overlap by time delaying the streams on top of each other, higher SNR. The other advantage of MIMO technology is that the more antennas you have the lower power they can each have, as the higher power isn't required to get an improved SNR for the QAM256 transmission. Less power means fewer waves from your neighbors interfering with your channels in our Bands... then there's the attenuation of higher frequency waves by objects being greater than attenuation of lower frequency waves.

Just try learning some radio engineering and realize that they actually ARE doing something intelligent when designed these chips. It's kind of what keeps them in business.

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gordon_tron

First, you seem to contradict yourself pretty quickly.
You wrote "There are no "2.4ghz/5Ghz" antennas. You can use an antenna and get both channels. "
-->my response: the "/" between between 2.4 and 5 means that it is a single antenna that can support both frequencies. Every device like iphone5, ipad, and some laptops have dual band 2.4/5ghz antennas. These kind of devices only have a single wifi radio, so it is either tuned to a 2.4ghz wifi or a 5ghz wifi channel, one at a time.
You can design an antenna to have good reception of both or many wavelengths, and this is not new and not even up for discussion.
Also, many "dual band" routers are also using 2.4/5ghz antennas to share between both AP radios, simultaneously. Look at a teardown of Asus RT-AC66u. It has 3 antennas, but it has two 3x3 wifi radios, one 3x3 in 2.4ghz, the other 3x3 in 5ghz, for a total of 6 Transmit/receive paths. But it only has 3 antennas.... How? Because the 2.4/5ghz antennas are SHARED between the two radios.. for the reason you did correctly state, because they are at different frequencies/bands.

I fully understand the concept of MIMO. I am a super-user of these home routers, and I know the difference between good marketing and real technical advancement. I have a an R7000 at home as my second Access point at the far side of the house, and it is broadcom based. it is a dual band device, providing my home with 2 additional wifi networks, one at 2.4 and the other at 5ghz. I have read multiple articles on this "new" wifi, and what I see is that they are just adding a second 5ghz radio, for a total of 3 radios. It is not true single radio 6x6. Reiterating my point from before, they are just adding another wifi radio inside the router, taking up another channel. Three total wifi channels will be occupied by this.
Anyone can do this. Why is broadcom calling this a new product? Because unlike Qualcomm and Quantenna who are releasing radios with mu-mimo, they still have the same stuff, but need to have some response to these new chips because they must not have mu-mimo coming any time soon. So, they take more of their chips put them together in a single box, and call it a new product. Im not saying its easy to stick a 3rd radio into a dual band router, I am sure there was some tuning of filters and other things, but this isnt a revolution... its more of the same.
You run into fake "breakthroughs" all the time in tech.
More on mimo..
Do you understand that normal "single user" mimo (su-mimo), if one side is 3x3, and the other side (like a galaxyS4) is 1x1, you are limited to 1x1 max rate? So, if you have a 3x3 router capable of 1300mbps at 5ghz, and you have 3 samsung Galaxy s4 or other mobile devices connected, the max wifi rate you get out of that "1300mbps" router is only 433mbps? Because all of your devices only suport 1x1 433mbps the router cant use 2 of its mimo streams. Yes, the 3 transmitter/receiver antennas get you further range but the "big number" on the box, 1300, is not what you are getting.
And given the consumer is moving to more mobile devices with 1x1 wifi, again, this is more and more just a big number on the box that cant be used.

Mu-mimo, on the other hand, is the future and truly an revolution of wifi. In that same scenario, mu-mimo (multi-user mimo) can send to all 3 galaxy S4 at the same time. So, your "1300mbps" on the side of the box can actually be achieved in the real world. Mu-mimo can break apart and send a single spatial stream to independent devices.
(I know samsung Galaxy S4 does not support mu-mimo, but phones and tablets are coming with this capability this year)

Now lets look at what broadcom is proposing, adding a second 5ghz wifi radio. Taking up 2 channels.
total throughput to these 3 devices is 433x2 = 866mbps
A SINGLE mu-mimo 3x3 radio taking up only ONE 5ghz wifi channel can achieve 1300mbps, because it can send to all three devices simultaneously. What if that radio was 8x8? A wifi AP can connect to 8 total devices at once...
Apply this to a hotspot at the airport...to an apartment building... to an office... as more and more wifi comes, the answer is to get more use out one channel, not add more wifi radios to your home taking up more channels.

See my point?
Trashing mu-mimo is stupid. it is going to happen. Broadcom will also get this new "innovation" on the shelf at best buy, and I am sure it will functionally work pretty well, but I would argue that there are few maybe no people who will actually benefit from it more than the R7000..its really nothing new. And I guarantee Broadcom will get mu-mimo some time in the future, and then you will see its story flip, its simulations change, and it will be the best thing in the world.

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Hey.That_Dude

Never bashed MU-MIMO. Great Idea. But you have to have the spatial stream support for such a thing. And it again benefits from multiple antenna. I'm sure that their products will suffer performance wise compared to Quantenna when everyone's Galaxy S5's want to connect to the Wifi... that doesn't even get feed faster than 25mbps for most of the United States.
I know how radio limitations work, EE. However, if their "Penta-core" *gag* DSP is updatable to allow for Mu-MIMO add on functionality (Which is all in the chip, not the antenna) then they would stand on good ground indeed (unlikely, especially given Broadcomm's nature). But, IMO, they are taking the most important step first, maximize bandwidth THEN add additional streams (which may or may not be practical given the limited channel capacity of the two frequencies and the bonding involved in these "higher bandwidth" applications).

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gordon_tron

wifi commments appreciated

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Ghost XFX

What good are they going to be, considering most ISPs have crappy service? I'd love to see 5G-10G service online, but hell, companies like AT&T and Cox Comm act as if they haven't even past 2G in some parts of the country. Constantly dropping connections or just in general ass dragging lag, and they have the nerve to want to charge you an arm and a leg for it!

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Hey.That_Dude

You realize this has nothing to do with 2G-3G-4G as you know it, right?

This is 802.11 wireless, also known as WIFI. The 5G thing is them mooching off of marketing jargon that companies such as AT&T, Sprint, and Version use to make their products look the same even though they are entirely different from a physical media standpoint.

I'm all for wireless carrier bashing, but this isn't the article for that. However, if you want to bash those same companies for not giving you FTTH, or another form of high speed internet close to 1Gb, then be my guest.

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vrmlbasic

Say I get 10 Gbit/sec or even just the 3.2 Gbit/sec. What do I do with it when all of my wired devices are still going to be poking along at a mere 1 Gbit/sec?

Could it be faster to have 2 machines on this 10 Gbit wifi transfer files wirelessly than to have them transfer directly via Gigabit Ethernet?

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Hey.That_Dude

In short, no. That's maximum theoretical throughput. Which you might get close to... if there were no other 5Ghz channels for 2 miles, you were 1 foot from your router and all the antennas had maximum power transfer to your router, with full channel bonding used.

The "10Gb" connection might get you 1 Gb/s on a good day though.

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jgregory1

While faster is always better than slower, an unreliable faster is not particularly desirable. The speeds discussed here are indeed high, but what I really want is a wifi connection that is fast ENOUGH to stream HD video without buffering or any interruption. Rather than constantly chasing after higher theoretical speeds, how about ensuring that the wifi connection is rock solid?

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LatiosXT

Unfortunately you can't, because that's the inherit problem with radio waves.

They should though, allow different topologies. What if you could do a mesh network?