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Date: Sun, 6 Mar 2011 22:39:10 +0000
From: Bruce Cran <bruce@cran.org.uk>
To: Adrian Chadd <adrian@freebsd.org>
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Cc: erob@gthcfoundation.org, freebsd-chat@freebsd.org
Subject: Re: can somebody explains OFDM in FreeBSD?
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On Mon, 7 Mar 2011 05:00:42 +0800
Adrian Chadd <adrian@freebsd.org> wrote:

> FreeBSD doesn't implement OFDM in the kernel.
> 
> The various chipsets implement OFDM, not FreeBSD.
> 
> There's no "software" OFDM. The 802.11 chipsets out there take care
> of it, not FreeBSD.

[moved to freebsd-chat]

OFDM doesn't exist in the digital domain. The furthest you can go in
software is to use the I-Q pairs that represent the modulated (baseband)
data - that is, QPSK, BPSK, QAM etc. If you have a card that makes I-Q
data accessible (and I suspect most wireless cards don't) then you can
demodulate it using general-purpose software such as Matlab or a DSP
library.

-- 
Bruce Cran