Any suggestions for programmable attenuators?

Any suggestions for programmable attenuators?

[Ben Greear]

In order to automate testing of throughput v/s distance, I am
hoping to acquire a programmable attenuator that can be
scripted and supports at least 3 connectors (for 3x3 NICs).

If anyone has any recommendations please let me know.

Thanks,
ben

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

Re: Any suggestions for programmable attenuators?

[Paul Stewart]

We have a few units from eubus (http://www.eubus.net, ATS0760-95).
They're fairly easy to interface to (we're controlling them with a
BeagleBone, but need level shifting because they are 5V devices).  We
don't have a whole lot of seat time with them so far, but we've
validated that they work.


--
Paul

On Thu, Jul 26, 2012 at 9:30 AM, Ben Greear <greearb@candelatech.com> wrote:
> In order to automate testing of throughput v/s distance, I am
> hoping to acquire a programmable attenuator that can be
> scripted and supports at least 3 connectors (for 3x3 NICs).
>
> If anyone has any recommendations please let me know.
>
> Thanks,
> ben
>
> --
> Ben Greear <greearb@candelatech.com>
> Candela Technologies Inc  http://www.candelatech.com
>
>
> --
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Re: Any suggestions for programmable attenuators?

[Ben Greear]

On 07/26/2012 10:29 AM, Paul Stewart wrote:
> We have a few units from eubus (http://www.eubus.net, ATS0760-95).
> They're fairly easy to interface to (we're controlling them with a
> BeagleBone, but need level shifting because they are 5V devices).  We
> don't have a whole lot of seat time with them so far, but we've
> validated that they work.

I've managed to wire up some of these as well (using Arduino as controller).

One thing I notice is that the smallest signal quality I can see
reported by the NIC (ath9k) is about -81 or -82 dBm.

Technically, the attenuator should be able to go below the
noise floor of around -90dbm if I understand things properly.

Have you done any testing of this nature?

And for what it's worth, using ath9k, 1x1 MIMO (one channel) /n, ht40 on 5ghz,
I get almost 8Mbps UDP download at -80 dBm signal quality :)

Thanks,
Ben

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