[CWN-Summit] beamforming outdoor AP

[Brough Turner]

The point of beamforming is to electronically steer a beam at a particular
destination under software control. The military has been doing this for
decades (e.g. for phased array radar), but it does involve extra complexity.

If fixed aiming is adequate, then obviously the Ubiquiti, or a home-brew
equivalent, is the way to go.

Ruckus is doing beamforming by "antenna element selection."  That's a lot
simpler than full phased array steering.  Basically, they have 12 somewhat
directional antenna elements pointed in different directions.  (They may
also have some switch selectable phase delays). Then, on a frame by frame
basis, they select which two of the antenna elements to connect to the 2
radio terminals on an Atheros Wi-Fi chip.

The Ruckus access points do work a lot better than the comparable Cisco
devices, if you are an IT guy trying to provide Wi-fi coverage in your
corporate offices. But I don't have any knowledge of what effective beam
widths they achieve or whether they work in other environments.

In the future, we can expect full phased-array beamforming in Wi-Fi chip
sets, i.e. at consumer prices.  Some leading indicators are these start-up
chip vendors:

http://www.quantenna.com/beamforming.html
http://www.celeno.com/Technology/


Thanks,
Brough

Mobile: +1 617 285-0433   Skype: brough
Blog: http://blogs.broughturner.com/


On Tue, Aug 17, 2010 at 5:06 PM, Stelios Valavanis <stel at onshore.com> wrote:

> you know these are $2k. you can build a dual-radio setup for $500 or buy 2
> ubiquiti's for $90 each.
>
> On Tuesday, August 17, 2010 02:39:35 pm Alexander List wrote:
> > Hi,
> >
> > we've been talking about beamforming outdoor mesh APs.
> >
> > I found one, but the bandwidths advertised don't really convince me:
> >
> > http://www.ruckuswireless.com/pdf/ds-zoneflex-7762.pdf
> >
> > The price tag of USD 2k is also quite steep, and it's all proprietary ...
> >
> > Alex
> >
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>
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