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RE: Amateur radio module on commercial Geo Sat?



> SSB wouldn't make a whole lot of sense here. Coded digital modulation
> (possibly carrying compressed digital voice) would allow much more
> efficient use of ground station and transponder RF power and make
> automatic doppler steering much easier. If modulation with a constant
> envelope is chosen (e.g., BPSK, QPSK, MSK, 8PSK, etc) and the channel
> is shared using time-division multiple access, then the transponder
> can be hard-limiting. This allows significantly greater DC->RF
> conversion efficiencies than can be attained with linear transponders.

Just one wee little question.  How would TDMA work, when there's stations
spread across a wide area (with vastly different, and generally large
propagation delays), without being either horrendously slow, or stations
accidentally falling out of their timeslots, due to propagation delays?

That's one of the limitations of GSM mobile phones in rural areas here,
incidentally.

Just curious how you'd tackle these issues.
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