Next message: Alexandre E Eremenko: "Re: Astronomy and Celestial Navigation"
Bill, there is some question of exactly how easily the military signals
(admittedly weak) can be jammed, but if you wanted to remove precision
navigation capability from a radius of two or three thousand miles (say, over
the Pacific and western Pacific Rim) it would require an awful lot of local
jamming stations. If you wanted to take out a five thousand mile range (a penny
in the bucket compared to the size of China) I suspect it would be cheaper and
simpler to knock out the satellites.
Or, build a clandestine GPS jammer into every cell phone made in Korea and
China. Lest you think that's unlikely...Furbies were banned from the NSA
facilities, and Lenovo (ex-IBM thinkpad) computers were almost banned from DoD
contracts a week ago, for the same reason: No one knows what a gizmo really
does, until you've taken it apart.
But for sailors that's no problem, any event large enough to take down the GPS
systems (plural) will probably assure vessels of a military escort once they
come within a hundred miles of any coast. With solid-state accelerometers and
optical gyros bringing inertial nav into the size of paperback books, that will
only be an inconvenience for military users though. The civilians with no budget
will have to rely on celestial, or their compasses, until they acquire an
escort. No big deal, just an "inconvenience".
