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RE: Re: Discovery Project: Which Mission Next?



> But on a LEO bird, what value is anything more than that?  
> Everyone in the
> whole USA would have to share just 15 minutes, and we have 
> demosntrated
> that that is difficult to do on LEO's

Indeed!

> 
> What I think we need is something like about a 1 second frame 
> rate.  This
> would only take 12 dB more than FM and about 250 KHz instead 
> of the 6 MHz
> for FSTV..  But rather than inventing another wheel, I suspect the mor
> universal approach will be just to have a high data rate digital
> transponsder, and then JPIG images can be exchanged just as 
> easliy...  ANd
> with the possible compression, this will be far more effecient thatn
> either FSTV or FAST-FM SSTV....
> 
> In any case, what would be a good target?  1 Image a second?

Well, with digital technology, it has already been proven that a useable (~
1fps) video channel can be obtained on a data stream < 30kbps.  Many people
do it everyday on the Internet!  So, it's not unreasonable to expect a
moderate bandwidth video  link vis satellite.  At 30kbps, this is within
current bandwidths and modem technology.

By the time you get to 64 kbps, you're at ISDN speeds, for which there are a
number of commercial videoconferencing systems capable of excellent
performance.  My point is that your idea is achieveable. Could be especially
good for SAREX and similar programs.

The real clever part will be in keeping the cost down to "amateur budgets",
to ensure widespread adoption of the technology (oh, and might need to coax
a few soldering irons out of mothballs ;) ).
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