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<H1>Sat-Nav threat from jammers</H1>
<P><FONT face=Verdana>BBC news reports on concerns that not only sat-nav users,
but also critical national infrastructure is at risk from attack from widely
available jamming equipment.</FONT></P>
<P><FONT face=Verdana>Jamming of GPS systems can be achieved using very low
power equipment.</FONT></P>
<P><FONT face=Verdana>An article 'Potential interference To Galileo From 23cm
band operations' mentions that a jammer running just 2 milliwatts is reported to
have disrupted GPS operation over a 1 nautical mile radius in a sea trial,
see<BR></FONT><A href="http://www.southgatearc.org/articles/galileo2.htm"
target=_blank><FONT
face=Verdana>http://www.southgatearc.org/articles/galileo2.htm</FONT></A></P>
<P><FONT face=Verdana>The BBC news article <EM>'Sat-nav systems under growing
threat from 'jammers' </EM>by Jason Palmer can be read at<BR></FONT><A
href="http://news.bbc.co.uk/1/hi/sci/tech/8533157.stm" target=_blank><FONT
face=Verdana>http://news.bbc.co.uk/1/hi/sci/tech/8533157.stm</FONT></A></P>
<P><FONT face=Verdana>Radioactive Networks - GPS Jamming<BR></FONT><A
href="http://www.radio-active.net.au/web/gps/jam.html" target=_blank><FONT
face=Verdana>http://www.radio-active.net.au/web/gps/jam.html</FONT></A></P>
<P><FONT face=Verdana>Southgate 2007 - BBC News - MoD set to block sat nav
systems<BR></FONT><A
href="http://www.southgatearc.org/news/june2007/mod_gps_jamming.htm"
target=_blank><FONT
face=Verdana>http://www.southgatearc.org/news/june2007/mod_gps_jamming.htm</FONT></A></P>
<P><FONT face=Verdana>Global Positioning Systems (GPS)<BR></FONT><A
href="http://www.southgatearc.org/guides/gps/gps1.htm" target=_blank><FONT
face=Verdana>http://www.southgatearc.org/guides/gps/gps1.htm</FONT></A></P></BODY></HTML>