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Re: TDMA - Reading the mail



Jon Ogden wrote:
> 
> I'll admit the idea of a digital voice satellite has been intriguing.  Yes,
> even to me who has railed against it in the past.
> 
> One question about a TDMA or CDMA type satellite signal:  How would one go
> about "reading the mail"  or joining in a round table QSO?  The beauty of
> analog is we all share the same spectrum/time space.  That is also the worst
> part about it as well.
> 
> So how would multiple people be able to listen, talk, etc. on a TDMA or CDMA
> channel?  How would things such as a DX pileup happen?
> 
> Perhaps the experts have answers that satisfy these questions and more.  I
> do not.
> 

Well , I am no expert , but in the land of IRLP , what we do is all connect to a
"reflector" so that all those connnected can hear each others transmissions and
talk to each other while everyone else is still hearing whats going on , now I
can't imagine why something like that couldn't be done on a digital satellite in
much the same manner ,since ( in a totally oversimplified way ) it is all just
software and tcpip packets flying back and forth( ok , so I am no engineer , but
I know it works for me on my IRLP node ), we use "speakfreely" to do the codec
at its lowest sampling rate (8kc mono) and all the node boxes are linux machines
, cuz they don't crash like windoze and we can do it on a 486 dx2 100 ;)

So once you make a contact with someone on the "relfector" , then you could say
that you would both like to do a private connection with each other ( as you
would have your own individual "node callsign" id's so it would be easy ) , so
you disconnect from the reflector and reconnect to each other, then you would no
longer be copiable by the other folks on the bird until you reconnect to the
"reflector" .......

Sound neat ? , well it is and works full time on the web , goto
http://www.irlp.net to learn more ( shameless plug , sorry ) , check out the
active node status page , and it doesn't use java ;^)


Ok , so thats the only time I will mention this cuz , we seem to be talking
about different ways to do digital voice through a satellite , and I think this
would be a neat way to do it , but as I am no expert , I don't have a clue as to
how it would be implemented , just thought I would give you speculators out
there something real to chew on instead of the AO-40 team ;^)

73's the solstice is here :^)

-- 
Douglas Cole   N7BFS
AMSAT#26182 , K2 # 544
Spokane IRLP node 145.250 owner
http://www.users.qwest.net/~cdoug3
Registered Linux user # 188922
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