Re: garage remote jamming

["Jeff Volp" <JeffVolp@xxxxxxx>]

There are two basic types of spread-spectrum transmitters.  The
spread-spectrum technique I described earlier is used by millions of people
every day in their GPS receivers.  Here is the reference:

http://www.navcen.uscg.gov/pubs/gps/sigspec/gpssps1.pdf

It uses a pseudo-random sequence to modulate the transmitter, and receives
through correlation with that exact pattern.  Knowing what we had to do in
those early GPS recievers, I find it amazing how cheap they are today.  The
wonders of commercialization...

The other technique uses a number of discrete frequencies, and the RF link
hops between those frequencies based on some sequence.  This is an easy
system to impliment with digitally tuned synthesizers.

As our RF environment becomes more polluted every day, techniques like this
will become more commonplace in our attempt to achieve reliable
communication.

Jeff