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RE: Amateur radio module on commercial Geo Sat?



> It's easy with TDMA to change the fraction of satellite capacity
> allocated to a given user by just varying the number of timeslots
> assigned to him.
> 
> FDMA and CDMA also require automatic power control at the ground
> stations (witness the chronic "alligator" problems on existing analog
> transponders).  With TDMA, you can just blast away without any harm,
> as long as you control your sidelobes towards any other satellites
> listening on the same channel.

Hmm, this is becoming an interesting thread, and some good arguments in
favour of TDMA for amateur satellite work.  Perhaps we should come up with a
list of pros and cons for FDMA, TDMA and CDMA.  Whatever transpires, we need
to venture out into this area of digital comms - high bandwidth, multiple
access digital birds.  I certainly like the way TDMA would eliminate the
alligator problem.  A big plus for us QRPers - everyone gets a fair go.  One
question I will ask, as I live close to the international airport here, is
what effect (if any) an aircraft might have on the link, if it passes close
to/through the beam.  I suspect little, because the main beam is trained on
the bird, so reflections should be a long way down, but I just wanted to be
sure.

In any case, at least we're talking positively about high speed digital.
That's a start.  Next is to actually _do_ it. :)
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