1) Many good resources pop up doing a Google search using
   these terms:

   basic xor "spread spectrum" "block diagram"

http://www.google.com/search?hl=en&lr=&ie=ISO-8859-1&as_qdr=all&q=basic+xor+
%22spread+spectrum%22+%22block+diagram%22&btnG=Google+Search


2) A practical introductory paper (for those new to modern spread spectrum
   concepts) with experiments using common/easily available parts:

 "A Direct Sequence - Spread Spectrum Modulator/Demodulator Design"

[PDF]A Direct Sequence - Spread Spectrum Modulator/Demodulator Design
http://www.oakland.edu/~msharawi/ds_ss_circuit.pdf


"This report described the design of a Direct Sequence-Spread Spectrum
system,
that included the design of the Modulator and Demodulator circuits.

The design and simulations were intended to give anyone who is in the
Communications field a very rough insight about such systems, which are
starting to invade the Telecommunication market. Or to be more precise, they
are already in it for years. But we started to see their wide spread
recently. So, this report describes how to design simple systems based on
the idea of DS-SS technique.
The design was a total success.

All the circuits functioned properly, and can be implemented easily to
demonstrate the exact behavior of DS-SS systems. As i mentioned before, this
design can be implemented physically, using available components like the
familiar 74XX logic family, and a couple of analog devices like resistors,
and capacitors."


3) Glossary of terms:

http://www.newwaveinstruments.com/resources/glossary.htm


RF Jim


----- Original Message -----
From: "Jonathan Johnson" <jonathan@OUTEREDGE.NET>
To: <PICLIST@MITVMA.MIT.EDU>
Sent: Tuesday, November 12, 2002 6:39 AM
Subject: [EE] Spread spectrum receiver/DSP problem


> Does anyone on list know how one would go about decoding multiple channels
> on a spread spectrum receiver? with different spreading codes for each
> channel but all being decoded by the one receiver?
> e.g. for a system that has  lets say 50 available spreading codes to be
used
> for diff channels, I want a receiver to be able to decode a number of
these
> simultaneously for instance channels 3,7,23,32,47.(not necessarily 5
> channels)
> The data for each channel could be output in a number of ways either with
> each packed added a channel id number to the end of it or thru different
I/O
> lines.
> I imagine this would entail some MAJOR signal processing. I don't know
> personally but this sort of  sounds like what a cellular base station does
> with multiple channels.
>
> You used to be a cellular guy didn't you Jim? have you any pointers etc
> where I could learn a bit about the techniques involved?
>
> No pointers or info will be turned down, I have no idea other than what I
> described above.
>
>
> Cheers
>
> Jonathan
>

--
http://www.piclist.com hint: To leave the PICList
mailto:piclist-unsubscribe-request@mitvma.mit.edu