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Old January 10th 05, 03:49 PM
David H.
 
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On Sun, 09 Jan 2005 09:46:20 GMT, "Wim Ton" wrote:

The ARRL published a book about spread spectrum quite a while ago. The
Brittish magazine "Electronics & Wireless World" published a 2 part article
at least 5 years ago.

Wim


Literally the last book I read that had anything to do with spread spectrum was the
1993 edition of the ARRL Handbook. I read enough of the basic theory to get me very
interested, and it's been stewing in the back of my mind ever since. Recently I saw
something the refired my interest once again in spread spectrum.

A Quote:

"Also, a 500mw spread spectrum device can easily have an effective range of over 20
miles. In 1994 I field tested a spread spectrum LPD/LPI handheld radio designed for
downed pilots. The power would vary between one half milliwatt to one full watt based
on the quality of a duplex link. With power levels below 25mw we could communicate
clearly at a distance of 45 miles on the open ocean (from a life raft), and 15 miles
in the dense woods of Maine. When the device was tested in a dense urban area, a
range of 2500 to 8600 feet was obtained while keeping the power output *below* 15mw."


I've seen two publications on the web regarding spread spectrum:

The ARRL spread spectrum sourcebook at:
http://www.powells.com/cgi-bin/biblio?isbn=0872593177

and

TAPR's Spread Spectrum Update at:
http://www.tapr.org/tapr/html/Fpub.ss.html

Has anyone read either of these publications? I'm afraid I'm just a little rusty on
the old algebra, trig and calculus. So a relatively math-free (not completely
math-free, mind you) book would be appreciated.

As I understand it, the ARRL spread spectrum sourcebook is evidently a collection or
articles put out by the ARRL/AMRAD on spread spectrum experiments. Would this be
correct?

Like I said, I'm a beginner in this area, but usually learn quickly. Is there any
such thing as, perhaps, a few "ready-made" kits or consumer devices that could be
immediately utilized in exploring this fascinating field? This would be very nice
indeed.

Dave