There are people already doing this using gunnplexers:
http://www.qsl.net/ke5fx/
After reading it, (and other pages) it looks like anyone who's somewhat
good with electronics, and already has access to the needed equipment
(scope, and 10GHz spec analyser), could probably create such a link for
under $500.
Because of the nature of the gunnplexer, it is half duplex and collision
detection is NOT easy. It also can only be implimented between two
points. It would probably make a lot of sense to impliment a simple
token passing (i.e. trade a token with every packet, keep it for x ms if
you have nothing to send, only send when you have it, if you dont get it
back for 2x ms consider the token lost and regenerate it) as a hack in
the ethernet driver.
Michael Anderson wrote:
> You could probably use the RJ45 (modular UTP) connector to get separate
> RX/TX signals as well. A third (and more expensive) option is to get a coax
> to fibre converter for the signal.
>
> The ID requirements could possibly be met by having a dedicated node on the
> wired network side that sends a broadcast (in the ethernet sense) ID
> somewhat more often than required (this will allow for delays due to
> collisions). I'm not sure of the UK requirements, but in the US sending it
> in plain ASCII every 8-9 minutes would generally ensure compliance.
>
> If you want to use such a system on a network with multiple computers (that
> is 2+ computers connected via wire) the radio<-->ethernet should probably be
> on the other side of a packet forwarding firewall for several reasons.
> 1. The firewall will prevent network traffic intended for the wired network
> from being transmitted over the air.
> 2. The firewall could be used to prevent other hams (or worse non-hams) from
> gaining access to inside systems.
> The firewall machine could also be the one that sends the ID packets, with a
> UN*X firewall the command could be run by cron.
>
> I am also very interested in the idea and have been thinking about it (as
> opposed to actually studying it) off and on for the last two years.
> Unfortuneatly I seem to have the same limitations--young family, limited
> financial resources... :(
>
> 73
>
> KF6LGN
