[ath9k-devel] Any 4x4 MIMO ath9k NICs coming soon?

[Ben Greear <greearb@candelatech.com>]

On 01/17/2012 02:03 PM, Galen wrote:
> Ben's company focuses on load testing applications, so I assume he's referring to 4 spatial stream systems. 4x4:4 specifically refers to 4 transmit, 4 receive and support for 4 spatial streams. The only commercially available chipset for 802.11n is from Quantenna.
>
> There are 4x4:3 802.11n chipsets available which use the extra radio for beamforming and diversity, but these are not 4 spatial stream. You get an improvement in terms of RF performance, but the MAC layer and throughput is essentially the same as 3x3:3 solutions like AR9380 and AR9390. Since Ben's application is primarily focused on these layers as far as i know, I assumed he was looking for 4 spatial streams.
>
> Keep in mind, beamforming and diversity is very much possible within implementations the 802.11n specification. The only thing really novel to 802.11ac is the addition of optional downlink MU-MIMO.
>
> -Galen
>
> On Jan 17, 2012, at 1:39 PM, Adrian Chadd wrote:
>
>> Well, are you talking about:
>>
>> * 11n 4x4 MIMO?
>> * 11ac Multi-user MIMO (where you map stations to separate spatial streams?)
>> * other beamforming/diversity stuff?

I'm mostly just passing on a question that a customer asked me.  I assume
they want 4x4 MIMO with 4 spatial streams.

I'll look into 11ac as well.

I'll also take a look at the quantenna offerings, but so far, Atheros is
the only manufacturer that has the driver/hardware support for the virtualization
that we need (since way back in ath5k/madwifi days), so I sort of assumed
that isn't going to change anytime soon...

Thanks,
Ben

-- 
Ben Greear <greearb@candelatech.com>
Candela Technologies Inc  http://www.candelatech.com