[BC] Amateur radio spectrum

[RichardBJohnson at comcast.net]

Not so. When you have a carrier that doesn't move. It is
an interfering bin that is always present. Any pseudo
random codes that hit that bin will have a data error
--forever. Any receiver that is close enough to detect
that CW carrier will will always have that error.
Not all pseudo random codes will have a bin that hits
that carrier, but most all will somewhere in the
sequence. That's why anything in-band that isn't
a pseudo-random sequence will shut down communications
in band. Spread spectrum nowadays, is bandwidth limited
so that something at 50 MHz isn't going to affect
the military communications using spread spectrum
in the UHF bands. Furthermore, the military spread
spectrum uses frequency jumping that can avoid bins
from interfering carriers. This is not an efficient
use of spectrum space either. As I said, ultimately
we will all be using spread spectrum, but they need
to kill off the quiet carriers first to make it
efficient.
  

Cheers,
Richard B. Johnson
Book: http://www.AbominableFirebug.com/

----- Original Message -----
From: "w2xj" <w2xj at nyc.rr.com>

Richard

You are pretty off base, here. Spread spectrum is very resistant to 
interference from CW like signals. The operation is reciprocal. just as 
the energy is spread over a wide spectrum for transmission, the receiver 
de-spreads that signal. In the process it spreads CW carriers back to 
noise. So the idea that some CW carriers can eliminate spread spectrum 
communication is incorrect.  How according to Shannon, the noise floor 
will have an impact on the maximum payload possible so the more CW 
carriers spread out during reception, the higher the noise floor. All 
that being said, I really think you are thinking of ultra wide band 
transmission which is a little different.