Timothy C Holtom wrote:
Can anyone out there tell me a good source of practical information
(schematics and the like) for building SS transmitters and receivers.
I'm particularly interested in how I'd design the part of the receiver
that acquires then tracks the synchronisation signal from the
transmitter (correlation etc)

I did an initial scout around on the net but the only stuff I could
come up with was TAPR but there's seemed to have been cancelled.

I'm into experimenting, and not afraid of math (an electronic engineer
from a long time ago...)

Can anyone help me here...

I have Dixon's text on spread spectrum techniques, but that's perhaps
Too Much Information. The TAPR has a book out on spread spectrum in
ham radio, which may be more to the point. Have a quick look at
http://www.tapr.org/tapr/html/Fpub.ss.html.

And of course a google on `"Spread spectrum" book` will give lots and
lots of hits on textbooks.

But as for synchronization, you have to know roughly where in the
FH or PN sequence the transmitter is, and then adjust your receiver
clock to sync up, and then do early-late tracking to keep the RX clock
synced up with the TX clock.

If I were doing it, I'd always start at the beginning of the FH or
PN sequence for each transmission, and build my receiver to expect
the TX to do that. Otherwise it starts looking too much like crypto
for me to want to deal with it.

--
Mike Andrews

Tired old sysadmin