On 06/03/11 05:39 PM, Bruce Cran wrote: > On Mon, 7 Mar 2011 05:00:42 +0800 > Adrian Chadd <adr...@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. > > Not sure I'm following well but thanks for the pointer. If a OFDM chipset have the required hardware to demodulate high frequency waves into the corresponding 802.11 layer using hardware interrupts, then it should also be possible to inverse the modulated data back into an electric current one way or another using the very same hardware and inverse DFT function as explained here:
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