Re: [Make-wifi-fast] Wiring up a wireless testbed

["Toke Høiland-Jørgensen" <toke@toke.dk>]

Bob McMahon <bob.mcmahon@broadcom.com> writes:

> A way I think about is to emulate the "system" in both range/power
> (attenuation) and in mixing (phase shifts)   It's a diagonal matrix for
> range feeding into an h-matrix for the mixing.  A butler matrix can be used
> for the latter if variable phase control isn't required, e.g. you don't
> care about spatial stream relative powers.
>
> On adding energy for "random" noise, some knobs of concern are the energy
> detect on the tx and signal floor for the rx.   These sources can be fed
> into the same h-matrix through their own d-matrices.  This won't replace
> field tests but helps get closer towards that while providing for repeat
> ability.

What equipment would it take to do something like that?

> Also, equally important by my judgment, though not related to wireless, is
> to synchronize the clocks on the PCs.  An oven controlled oscillator and
> PTP works well towards that goal.

Yeah, already using PTP in my testbed; quite essential for measuring
one-way delay.

-Toke