On Mon, 22 Dec 2003 17:46:51 GMT, (Derek
Lyons) wrote:



And then the secondary system gets targeted PDQ...

AFAIK, against a good spread-spectrum system, you won't do much better
than to be able to monitor the total energy with a broad-band
detector.

Spread spectrum systems also tend to have much lower transmitter power
than conventional systems - by Shannon's channel theorem, the channel
capacity is proportional to the bandwidth, but only grows
logarithmically with transmitter power. So you'll need a lot less
power for a given bitrate with a wide channel.

The net result is that you can only detect the energy of the
transmitter above background noise when you are fairly close to the
transmitter.

I'm really not sure how quickly you can count on taking out a spread
spectrum transmitter. Especially when it's put on a low duty cycle
transmit mode rather than a continuous transmit mode.

To be realistic, I'd anticipate that anything that looks like an
antenna farm would be bombed, and that some anti-radiation missiles
(presumably looking for signals in the known bandwidth that the enemy
uses) might be left "loitering" in areas that are likely to contain
transmitters (ones with good lines of sight). I suspect that the
former might be more important than the later. Prepatory intelligence
work (like bribing or having agents follow service people) would also
be a factor in locating transmitter sites.