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TCP-group 1994


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Military HF



As an ex-AWAC-er I can say most satellite links suck when running wide-band
secure, and are almost acceptable for narrow band.  The problem is they put
the satellites in orbit where everybody lives, and of course most wars occur
in some two-bit country.  HF is fine for Link-11 data between the Navy and
Air Force, but narrow band secure sucks.  The Air Force spent some big bucks
on the Chirp Sounder - where a ground station would walk up the HF band, and
the users would track it and display ionosphere conditions.  It turns out
that coordination is a bigger problem than propogation.  20 ships and 4 or 5
orbiters do NOT change frequencies lightly - so they tend to stick to one
frequency and don't care when it doesn't work.  If the threat gets too high
the clear voice syndrom takes affect and operators abandon all the gold
plated radio bo-jive...  The Only great satcomm I ever saw was during Grenada
and Panama.  Like I said, the satellites cover the U.S. pretty well...

The gadget that gets my attention is JTIDS.  This is a spread-spectrum data
and voice link - let's say 1 GHz for generality.  During the Iraq war we would
link the three forward E-3's together.  Then we would UHF Link-11 to the NSA
bird, and the pin-heads in the pentagon could get the air picture in real-time.
An added plus was the digital voice channel and the E-3 over Jordan could 
talk to the E-3 over the Northern Gulf.  That was done by digipeating thru
the central bird. Plus the Army SAM sites were equipped, and could relay.

That's the future.  I'm sure the NSA birds are retrofitted or are budgeted,
and the Officers trying to make General are jumping off the HF and SatComm
billets!  By the way, the satellite we used over Saudi was defective.  The
engineers who rode several missions concluded that the beam shape could only
come from a bent antenna... It worked real well over Riyadh, and faded to
barely acceptable up on the border.  You can bet a commercial AM station
would know what it's beam pattern was - before the customers arrived :-)

I think Hams, given the spread-spectrum go-ahead can start designing something
truly valuable, rather than AFSK toys as we are now.
--
n5owk





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