From owner-freebsd-wireless@FreeBSD.ORG  Wed Aug 27 22:42:03 2014
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Date: Wed, 27 Aug 2014 15:34:28 -0700
From: Bart Kus <me@bartk.us>
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Subject: FreeBSD TDMA: Legalizing 440MHz 802.11 modems
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Hello,

I'm wondering if you can tell me if it's possible to modify the FBSD 
TDMA code to make this card:

http://www.doodlelabs.com/products/radio-transceivers/sub-ghz-range/420-450-mhz-dl435-30/

legal to use in its intended spectrum.  By default the card violates two 
Part 97 rules:

1) Emissions are limited to 200kHz bandwidth
2) Symbol rate is limited to 56kSym/s

Is it possible to slow down the subcarrier symbol rate in that Atheros 
chip?  Is it also possible to then space the subcarriers tighter 
together to respect the 200kHz emission bandwidth limit? They'd have to 
come closer together anyway to uphold OFDM subcarrier orthogonality.

Thanks for any clues,

--Bart

PS: I'm asking in the interest of the HamWAN.org project.  We're trying 
to find a more mobile solution, which penetrates through forests and 
some buildings.  440MHz seems to fit the bill, but hardware is really 
hard to come by.